Is this my period?

So my period came (I think)  yesterday after being 13 days late. I traveled to Mexico and was stressing about it so I get that that would push it off. I also took two tests in Mexico and both were negative but now I'm bleeding and it's a whole lot lighter then normal. Usually I use super plus tampons but the light ones are doing fine. It is dark red and I do have cramps but it has never ever been this light. Is this my period? Could it be spotting? Help!