confused

So I had af Jan 16. Around feb 6 I started getting pregnancy symptoms. Nausea/ vomiting  dizzy fuller breast , sensitive nose congestion always hungry and food asversions but went to the dr on feb 14 and urine test was neg blood hcg was a 1. Still have the symptoms and have been having dull cramp for a week. Took a test last night saw a faint line and then disappeared. Took one this morning with second morning pee.  BFN!  Also tried to get frisky with the hubs and had to stop because it hurt like wasn't going in. Doesn't really happen to us. Help!!!!! Also my periods are  very irregular