Is there any chance that I have tested too soon and could still be pregnant?

I am on day 32 of my menstrual cycle. I have quite irregular periods and can get my period any time between 28 and 38 days. I have had pre menstrual cramps like my period is coming, all week. Usually they only last about 4 days then I get my period like clockwork. My are sorer and larger than usual and I kept getting a queasy feeling in my stomach all day yesterday. Just took a pregnancy test and it was negative (one of those tests you can take 5 days before your expected period). Is there any chance that I have tested too soon and could still be pregnant?