Spreading rash behind knee? I need your knowledge!

Developed a condition that started as what looked like 7 flea bites spaced out behind my knee.. Took a shower one night and scrubbed it with soap and hot water a little harder than should have because it itched severely.. The next day what looked like flea bites turned into bright pink and red spots that spread out over more area behind my knee.. small dots speckled down the back of the calf.... Also on the shin there are raised red bumps like lines that itch tremendously, hoping they're mosquito bites... Play a lot of sports, basketball, martial arts.. so do spend time sweaty... try to take showers asap.. also go to a cousin's house where cats rule and are allowed to roam everywhere, so that could be an issue as well... Hopefully the photo explains it all

[DHiggz21]

Thought i added a photo...