hi...I woke up with some skin irritations. one on my right arm it was round red and looked like something bit me. I had the same thing on my right hip. both were Itchy and red then a saw a welp on my right side of my back that also became red and itchy. all of these are on my right side of my body. I sleep on my right side most of the time and this was after sleeping in a bed that someone else slept in. I changed sheets and sprayed disinfectant. but im wondering if something could have bitten me or what it could be, can you help me?