If I saw you in the clinic I would "pop" your blisters. I'd also want to see the shoegear that you're using so that I could tell you what's wrong with the fit and recommend some type of insert that would give you the proper support or offload certain areas. Unless you have fallen arches or there is a problem with your shoegear (aside from infection, trauma, or other cause) you don't normally get blisters in your arch. Of course my assumption at this point is that the blisters came from pressure. They could very well be from one of the forms of athletes foot.
Don't soak your foot after you've popped your blisters unless you want to risk an infection. Triple antibiotic and bandaid until it heals unless it starts to get macerated in which case just a bandaid daily.