I need help

Rachel
I still have had no period since July! I have a ton of bloating and cramps. One day of the month I have a blood streaked mucus. The last two weeks I am very bloated and it hurts. No period. No sex drive, extremely tired. Doctor did lab work and of course found nothing. I went from heavy bleeding all the time to none at all. I am on Thyroid medicine but it is not helping. Ob doctor has no answers so I guess a fertility specialist maybe able to help more? I am 35 and was tested for Premenopause and it came back negative.