What Causes Spotting, Nausea And Dizziness After Unprotected Intercourse?

Hello my husband and I had unprotected sexual on Friday, around 2 weeks after my period ended, on Tuesday I started spotting. It comes and goes, not enough to fill a light tampon or panty liner however today is the 7th day I ve been spotting. Same consistency, no changes, off and on all day. I also am extremely exhausted and am diZzy in the morning and nauseated after eating. I don t have health insurance and my doctor won t see me without a positive pregnancy test but it s way too early to get a result. I m getting scared because the spotting hasn t stopped or lightened. I am just trying to find out if I should be worried or just wait it out.