Can I be pregnant? Or am I being paranoid?

I had my period this month, but the month before it was late by 2 weeks. So I don't know if out was because it was late that it interfered with my cycle. Anyways week after my period this month I was spotting. Today 2 weeks later I have felt nauseated. My husband and I did have ntercourse during my ovulation last month. I took a pregnancy test but it came negative and it was a cheap kind where I had too pee in a cup and get a dropper to put my urine sample on it, but the cup I used had water in it. I also have ben having cramps and feeling lightheaded. Is it possible that i'm pregnant? Yes I put this in two different places