I Have An Irregular Period But I'm On Day 28

I have an irregular period but I'm on day 28 now and usually I would have cramps a few days before but the only cramps I've had were a week or two ago and it wasn't like period cramps they were pinching cramps it felt like. I've had to urinate more and more everyday. I get so nauseous and dizzy off and on throughout the day. I have a creamy clear to white discharge and my cervix is high firm and closed. My right breast is very tender on the outside and I tested today but got a negative. Could I be pregnant?