Someone please leave their opinion!!

I am a college student, sexually active with my bf but we always use protection and make sure the condom didn't break or whatever. And I know I am not pregnant. 
I been under a lot of stress, academic and personal wise. 
2 months ago I menstruated twice in the same month. I menstruated for only 4 days the second time (usually lasts 5-6 days). Last month I got my period around the normal time. This month I am about a week late. 
Am I just over thinking it?