5 weeks along...ex thought i was lying about pregnancy....have no clue what to do?

Leave him alone and avoid all drama. Once the baby is born, get a paternity test (court order if he won't do it voluntarily) then get your child support and move on with your life. If he wants to man-up and be a father, let him, but don't be chasing him around trying to get him to care about you or the baby you're carrying, because you can't force someone to grow up.