rashes and bumps

gracie

for a while i have had this thing on my leg as seen in the first picture and im not sure what it is.... if im sweating or hot it itches like mad

and this morning i found my chest and around/ on my boobs are a rash and its quite bumpy and itchy

This picture was taken 2 hours later and the rash spread acriss all my chest and my neck... have any suggestions of what it may be or how to cure it?