Kinda concerned!!!

Mariah
So I've taken MANY pregnancy test. All coming up negative or inconclusive. I've had one that you could tell was positive and the rest were negative or inconclusive. But today I started what I thought was my period, but it's not like my normal period normally I'm seriously heavy, always bleeding through, but this one is really different. It's very light. Like barely bleeding light.. but I have cramps and everything.. so I'm actually very confused.. so can someone please give me some insight on what could possibly be going on...??