I Just Was Scratching What I Thought Was A Bite.....then

I just was scratching what I thought was a bite.....then I looked at it because I could feel it felt like more that one bite. It is red( looks blood filled) and bubbly feeling ....3 inch long by 1 inch area on my lower backleg..betw . knee and ankle Washed it ,rinsed w/peroxide now have neosporin on it ..it was itchin very bad looks like red blood blisters...????