im panicking

I have tiny cramps and I’m spotting. I’m 4 days late. I don’t know if this is my period or something else. It looked like redish. It looks like there’s a brown spot but I can’t tell if it’s just my underwear or if it’s brown or blood. Someone help please. I’m panicking and scared and I don’t know what to do

Edit: should I buy a test to be sure?