sounds like overstim... did they see how many eggs you had?.. I didn't bloat at all with my injectables..
I bloated up something terrible after taking injectibles, and I'm STILL bloated, 10 weeks later! I gained about 4 or 5 lbs. My ovaries are still stimulated and unhappy. I'm 36 btw, so pretty close to your age. Bloating is totally normal with injectibles.
The small bit of blood makes me wonder though if your IUI worked and you were getting some implantation bleeding? I think I had implantation about 6 days after my IUI. I'm now 10 weeks preggers. :)
I hope that's what it was for you!!
Sheri