Pregnant?

So, I missed my period. 2 weeks after I had sex I took a test and it was negative. A few days after that I took another test and it was negative. I still haven't started and I'm a week late, but I'm also cramping. This isn't the first time my period has been late, but it hasn't done it in a while. I've also started exercising and started eating healthier. Could that affect my period? Should I take another test? I don't know what to do. Please help.