What happened to my outlets?
A connection burned out

Outlets are typically wired in a chain.  One of the wires was making poor contact, and the high but allowable load burned out this poor connection. 

It will be on either the last good outlet in the chain, or the first bad one.   It will be on the white wire.  

If the connections involve the wire jabbed into a tiny hole in the back of the socket (not directly under a screw), that is a backstab. They are notoriously unreliable for this sort of thing.  Most of convert to either screw terminals or screw-to-clamp type connections anytime we see a backstab.   

We know it's not a GFCI because you get a hot indication.