How do you know when your pregnant if you have degenerative disc disease ?

I have gotten an MRI which diagnosed me having the disease but, I also have symptoms like dizziness nauseousness, and hot and cold flashes from this disease....i have taken a pregnancy test and came negative..that was three weeks ago....i also just recently stopped taking cymbalta which has made my mind messed up...(i ran out of it)...i also have no insurance because i recently moved so i can't just go see a doctor...idk what to do...and please don't be rude...help?