So, I'm hoping this is the best place to post this, because I'm kind of freaking out. Sigh, here goes:

So, recently I met up with an old friend from High School. Turns out, we had very similar situations and had a lot to talk about in regards to sex. She was very open and accepting of sexuality, and that made it easy to talk to her about my own sexual issues, which was a huge relief. We've been just hanging out on and off for a few weeks, nothing 'romantic' going on. But we do tend to talk about sexual things fairly often.
Now, just the other day, something came up. Somehow, someway, we were talking about the possibility of, well, doing stuff together, namely for my sake. As in, she knew I'd never done anything sexual with anyone, and well, frankly, she's done rather a lot of sexual things with people. So, we agreed on what was Ok to try, we'd go at a pace we were both comfy with, and that this would just be in the interest of helping me try something new.
So, after a solid 24-hour period of me being in a state of consistent anxiety attack, we met up and did... stuff. We each stuck with the boundaries we had discussed (my only huge requirement was that full-out intercourse was OFF the table), and were both quite respectful of one another. All in all, I'd say things went about was well as they could have gone.

Thing is, I'm doing more freaking out now than I was before or during the act.
I'm a mess of conflicting emotions, thoughts, and worries.
Namely, I absolutely don't want this to jeopardize our friendship. We've talked extensively about that. Both before and after. And I promised to do my best to not be 'weird' about things, something I'm confident she will do in return. This isn't the first time she's done this for a friend, after all. All the same, I worry.
Secondly, I'm having something of an identity crisis, now moreso than ever. Simply look back on this topic to see how I've struggled against my sexual impulses my whole life. Now, that's starting to change, and that's putting me in a very weird spot. My aversion to sexuality defined me in many ways. As conflicted and terrible as it could make me feel, I was at least secure and comfortable with familiar struggles. Now, that is all starting to change, and that's scary. It feels like I don't know who I am anymore.

I'll of course be talking about this with my Therapist and, more importantly, with my friend. I just felt the need to get this off my chest and see if anyone had some advice or a respectful opinion to share.