Late Third Period after stopping birth control

I had been taking birth control for more than 3 years (Seasonique, only got my period every 3 months) and I stopped in February, got my first period two days after, and then my second period 38 days later (I always bounced around with my numbers) and now I am at 102 days waiting for my third period. I have taken two pregnancy tests and a blood test and all have come back negative. Could it be that my body is still adjusting to not taking birth control pills anymore? Does anyone have suggestions of what it could be? (I've tried going to a doctor, but he said that no tests are done until a year after stopping birth control)