What Causes Cross-eyed Vision?

i suddenly started seeing like i am crossed eyed. i went to get my eyes checked and got new contacts but it does not goes away and it is making me very uncomfortable because i have this all day and all night. and i can't drive or do a lot things like i normally did. I am not under any medication. my vision improves if I tilt my head down or if I just look up. i did have a lot of headaches but not anymore since i stopped doing pull ups. it gets worse at night. if i focus on something the cross eyed is even on both eyes meaning the objects are right next to each other not one above the other, very clear and if I cover one of my eyes it goes away. I am in a very uncomfortable spot right now. I don't have insurance and I will be starting a job soon.