In my own personal experiences, there are two men that a woman will always remember having sex with: the first and the last. Fortunately the second of these two has the opportunity to change. The first never will. I don' think I care to be remembered by a woman forever at this stage of my life, I don't want to be first, I just want to be next so if given a choice I would opt for the experienced woman.
That being said - it is, of course, your choice to whom you give yourself, and when. Perhaps your bf needs to be reminded of this, and should be grateful for the exquisite bj's you're willing to bestow upon him.
It is times like this when I pause for consideration,
taking into account my known and suspected flaws both in character and personality,
reflect upon my self-impression of individuality,
and ask myself with great wonder,
"Why the HELL did I click this thread like a brainless sheep?"
I find it amusing that any single particular event could "turn you gay." It's not like being bitten by a vampire and you are no longer "human." Or having sex makes you no longer a "virgin." Being gay, bi-sexual, or hetero - none of these are something you can catch like the flu. Seeing another man's penis in the locker room showers isn't going to "turn me gay" either. Worry less about labels and worry more about what feels good. For the record, I find that I quite enjoy pegging.