3 weeks late!

So I am three weeks late and I have taken just about every test! Clear blue, first response, 88 cents one from Walmart, and digital. I am at a loss as to what to do! They all keep coming back negative and it's driving me crazy. I don't want to go to the doctor and be disappointed but idk whaty to do! I have headaches, tired, sore nipples and boobs, cramp on one side, pain under my belly button, nausea, and having to pee a lot! Tell me what to do!