What is this rash? Bump to rash after scratching.

A little background:

1. Started off as one bump.

2. Scratched, it was fluid filled.

3. It quickly became multiple bumps after fluid leak and spread.

4. It is itchy most of the time.

5. Located on leg (anterior) near inner thigh, smack in the middle, not close to anything else.

6. It's been there a week.

Any ideas what this thing could be? Treatment options?