I don’t understand!

I need opinions. I have been TTC for a year. I have had day 3 blood tests, HSG, day 21 blood tests, and my husband has a perfect Semen Analysis. I did 3 rounds of Clomid, 2 of those with IUI. Nothing has worked. Just this past Friday, I had laparoscopic surgery and D&C.; We really thought we were going to find Endometriosis. I have had terrible cramps my entire life, but there was no endo! I had the D&C; because when my doc has done my IUIs, he has had a hard time getting through my cervix, as it is “stenotic” or stiff...and i have a retroverted uterus. He wanted to dilate my cervix so that it would be open for one more IUI before I am referred to the RE in December. I am just so confused. If it’s not endo, and all my other tests are fine, what other possible problems are left? There seems like nothing else to even search for? I know i am 34 but could my eggs really be that bad by now when people all around me are pregnant and are older than me? I don’t understand! I’m so frustrated. Any ideas are greatly appreciated!!!