Red bumpy rashes on my legs?

Last night i had a large rash on my legs... For no apairent reason. It itched like crazy, and i woke up to having another. I also figured out its contagious.. Because i touched my cousins calf with it by mistake.... And soon after she got the bumps to!! They are close together and look like acne. I dont know if this helps but i have been scratch by my outdoors cat and bitten by mosquitos recently