Should I even bother seeing if I like bottoming?

I'm getting older and after all the sex I have had being the dominate and quite recently the submissive with women and dominate top with men it seems I have done every sexual thing I ever wanted many many times and most of the stuff I was talked into trying more than once I am thinking I want to complete the set and be a submissive bottom to a switch guy who has been pressuring me into it. Being the submissive for just one women was pretty hot BUT... I have had a lot of prostate massages and fingers inside my anus and thats been great, I also was "done" once when I was real young and don't remember any pain or pleasure and it was quite a short encounter. But when I put in a long dildo in me must be about 7 inches way past my anus deep inside at the "second door" I feel what my brain derives as pain when thrusting it and I don't like it at all. So is this a you got to get used to it to get to the point of enjoyment once the brain figures out how to process it correctly? When I have "trained" people into receiving anal sex from me they rarely complained of "deep inside pain" just the occasional stretching to let devices and my penis in. I've been told many many times once you bottom your hooked like a junkie but I can't see it that way right now. Also if any person out there has tried receiving once to many times and never got to like it do you know why?