Hi, I Have A Large Blister That Was Filled With

Hi, I have a large blister that was filled with puss and popped on its own as it rubs against my pubic area/underwear causing it to be very painful to walk. Over the last few days, 3 other blisters have forms around it, although quite a bit of space between them all so although I am worried it may be genital herpes it doesn't look like the images i have researched. I have also got one on my other thigh, closer to my anal area. Could these be a sign of STD???