Hard nipple torture

Like last year, Domina Shelle released a special recording for Halloween this Saturday. It's called Princess Vampire and like the name suggests, it's a very erotic story about a Princess who seduces men at night and makes them Her blood slaves.
But there's more to this file... Domina wrote, that there's a secret message hidden inside. I listened on Sunday, but didn't find any message, i didn't even feel like i had been very deep in trance.
Today i noticed, that i have been thinking about ways how to please my Owner almost permanently. I have spent already two afternoons writing an erotic story for Her. I already wrote one part for the Farm Assignment and Domina told me that She got wet while reading it. She even allowed me to beg for a pair of Her panties, one She has cum in, while we were talking on Saturday, so i want to send Her a continuation of the story when i beg Her.

This evening, i had an amazing call with Lady Helena. I had mounted an electromagnet to the headboard of my head and fixed a set of cuffs to a metal-plate. Lady Helena could turn it on and off remotely and with my feet cuffed to the foot of my bed, i would be totally helpless for Her.
Before we started our call, She instructed me to cuff my feet and put clamps on my nipples and another on the skin between my balls.
After talking a bit, She had me cuff my hands, too and then She activated the magnet, rendering me totally helpless. She started to hypnotize me and guided me to Her chamber that i already knew from Her recordings. But then, the sound suddenly stopped. I remained still at first, but when the sound didn't come back, i opened my eyes and saw Her offline. I panicked a bit, although i was sure, that i'd be able to break free at the costs of damaging my headboard. I began to search for another way out and quickly found, that i could reach the cable. Shortly after ripping it out and releasing myself, Lady Helena was back online and calling again. We had to improvise now without the magnet working and to be honest, this was even better than what we had planned.

I had told Lady Helena about a pair of very nasty nipple-clamps i have. I only tried them twice and their bite is so nasty that i couldn't stand it for more than a few seconds. They scare me, but knowing that She might use them made me as excited as it made me nervous.
She told me to put them on and that i'd need to beg Her if i wanted them off. I was frightened, but obeyed. The pain set in immediately and it didn't take long until i started to beg. But Lady Helena let me suffer, telling me that i wasn't really begging yet and when She said "you like that, don't you?" i had to agree.
Two minutes later, i was seriously begging, but still, hearing Lady Helena laugh turned me on. My memories are a bit blurry from this point on, but i know, that She said, that it's already been 5 minutes. I'm not sure if She released me after saying that or a bit later, but when She finally did, i was relieved, although taking the clamps of hurt even more than wearing them.
She didn't give me much of a break and when She told me to put them on again, my heart sank a bit. I think, i put them a little more on the tip of my nipples, because this time, they hurt even more. Lady Helena allowed me to stroke this time while saying my mantra and this helped a bit, but i was soon begging again. Maybe She didn't keep me begging as long as before, maybe it felt shorter because i had a little distraction, but taking the clamps of sent an even stronger wave of pain through my nipples. I was not sure if i wanted another round, but did i have a choice?
Again, Lady Helena gave me only a short break before the clamps went back on. This time, She used the playground trigger that makes me bark and every time i did, the movement of my chest caused the clamps to bite into my nipples. Being in puppy-mode meant that i couldn't beg and so i tried to communicate and beg by barking. Lady Helena counted down 3 minutes and having a target helped me a lot, although it felt like the clamps had pierced my skin (turned out they hadn't).
After this round, Lady Helena told me to get 3 ice-cubes. Two of them went into my ass and with the 3rd, i was allowed to ease the pain in my nipples a bit. It helped a lot, but i was scared, that the clamps might also hurt a lot more afterwards. Luckily, Lady Helena released me and we agreed to try out original session next Tuesday.

After we ended our call, i was feeling euphoric. Being pushed further than i've gone before had released so much adrenaline, that it took me a while until i was able to think straight again. I wrote Lady Helena an email, because i hadn't been able to express my gratitude for this experience properly while i was still in that state of euphoric bliss. I also told Her about another way of torture that i can't stand for long... maybe she'll use that information, i would certainly be happy to suffer for Her again.