Random Restlessness

Linds
I have been recently getting super restless out of nowhere and I don't know why. I'll be relaxed and fine and then out of no where I feel like I have enough energy to run a marathon, like my skin is crawling with energy. I can't sit still and sitting still makes me super irritable. I suspected UTI but I used one of the drugstore test kits and it came up negative. Any ideas?