Period or pregnant ?

So I had my daughter 6/25/17

I’ve had my period about 5 times since then because I bled twice after 2 weeks (so twice in one month) I got 3 days ago what I think is my period but it’s weird never had a cycle like this I started spotting (dark like old blood) then it stopped the whole day, the next day had bright red (light flow) then yesterday it completely went away.. nothing the whole day. But I’ve been cramping since 4 days ago. ? & yes I’m on birth control but could I possibly be pregnant ? Or just off cycle