Bathing suit rash help?

I have been wearing a bathing suit for the past few days even to sleep after going in and out of the ocean and I felt the irritation as I was walking and came home on the third day of nonstop bathing suit and slept in it. I woke up this morning and went to the bathroom and had one blister or zit looking thing, I popped it and it bled. The zit thing was right along where the bathing suit covered. I'm a 15 ye old male