I am no expert on the matter but I think it is soooo different for every women not to mention from cycle to cycle. We had our first collection when I was 21 and I was terrified beyond belief. I think I cried the whole way in the car and was crying like an idiot until they gave me a sedative (or something like that)! I had not recovered at all well from my laparoscopy and had worked myself into an absolute mess. My first full cycle we got 5 eggs and to be honest I did not feel a thing! The second full cycle I think we had 7 eggs but oodles of follicles and the procedure itself was a little uncomfortable but not painful but had slight OHSS and that wasnt nice and the 3rd 17 eggs and again procedure was fine, I was nauseous before then was admitted to hospital for OHSS. I think what I am trying to say that in my experience and it is only my experience the procedure was not painful for me and the OHSS was the worst part. Ive since had another laparoscopy and I still think it is much worse.
All my collections took about 10- 20 minutes each, I was put on an ultrasound table with my legs in 'leg huggers'. We were able to watch each follicle being drained. Our Nurses were extremely beautiful and until I started poking around and being nosey I didnt even know the tubes sitting on my belly were being filled with stuff from inside me! And to be honest it wasnt until my 2nd cycle that I was 'aware' enough to realise my Dr used an ultrasound probe, sounds stupid but I hadnt thought about how he could see my insides on screen!
If you want to know whats going on in there, ask your nurse while things are happening. Im sure I drove them nuts with questions but I was very curious. I also made a point of walking in and 'saying G'day' because everyone was being so serious and I didnt like that atmosphere either.

Good luck with it sweetie and I hope it isnt as bad as you think. I do hope this is the start of a very quick IVF encounter and you have a bub on its way soon......