What Could Cause Headache,fluttering Of Stomach And Bloating ?

Hey I have been feeling a little strange like I could be pregnant.. I had unprotected sex November 3... Like a week or so later I started having funny feelings in my tummy.. My head has been hurting everyday, my lower back started to hurt, I've been eating a lot , feeling sick in the morning & night but never throw up..My irregular period was last from nov. 15-19 (a few days early).. A week before it came on i had a cold for 3 days & was getting the pms symptoms.. Never got them before my period came on... So a few days after it came off my pms symptoms started back.. I had been having fluttering feelings in my stomach, bloating, gassy & like little sharp pains will come & go in my uterus area ... I took a pt before my period had came on & one line appeared.. Either I was going crazy or something but I did see another very very very very faint line too.. Like today I'm feeling very funny on my left Side of my tummy like something is scretching.. COULD SOMEONE PLEASE TELL ME WHAT'S GOUNG ON!!!! Is this regular for early pregancy or what?????