Spotting on concerta?

Hiii all!!

I recently started concerta (something like 3 weeks ago) and I've been loving it. Currently on 300mg Wellbutrin and 36mg Concerta.

I had my periods 11 days ago, but I am still spotting. It's unusual for me. Did anyone have same problem? Does concerta influence our reproductive hormones so much? What would be the long term implication?

Thank you so much!