I had what I thought was prostate pain. A buddy of mine said it was normal and should pass, and it did. I actually (this is gonna sound strange) had sex, and later took a good poop and the pressure/pain was gone..... sounds wacky but he suggested it and it worked. His theory was "All your pipes are backed up and the hormone changes aren't helping, you gotta clear the pipes".... lol. I feel retarded even mentioning it but since you've got some similar experience you might try that. lol.
So I know Osta is mad supressive, more than ppl like to think it is from what I've read. I would watch it closely, there could be pain b/c they are atrophying right now and will shrink over time. I can see that causing discomfort.
You've got a good PCT planned out right? Clomid or Nolva and perhaps a standby AI? Just keep an eye on things, we're all messing with our hormones so strange **** may be expected, just have the right supports and PCT stuff on hand and you'll proabably be fine, even if you get a lot of atrophy.
How long were you planning on running Osta (btw I had bad sides from it so I never ****ed with it).