I have blisters that have come up for no apparent reason on both of my big toes.

[Pam27291]

They itched at first but not anymore.  There is a clear fluid in them.  Each toe had a large blister about the size of a pea, with a couple of smaller ones.  I've had them about 2 weeks.  The blisters on the right toe broke and are healing, the left toe is still blistered.  I have only worn flip flops for the past 6 weeks so it isn't from shoes.  I went to the Dr. who told me it was not staph, or athletes foot.  She didn't take any samples.  She researched for about 30 minutes but couldn't come up with a diagnosis. sent me home with an antibiotic to use ONLY if the fluid turned yellow or looked infected.  Any suggestions on what it might be?