Help?

I honestly don't know what to do? Like I'm not sure if I'm pregnant because I took a pregnancy test and I could seriously barely see the lines but it was positive, and by barely I mean you had to squint in a certain angle. But what I'm worried about is that it's a cheap pregnancy test from a dollar store, so I'm not entirely sure it's a good test, but I'm getting cramps so I'm guessing I'm getting my period, but I read thatvit could also mean the uterus getting ready for the baby so I really need help, well advice or just some reasoning on how I might not be pregnant or if you know how to tell