Your treatment may not have been sufficient. Please read my comment to nymom815. I had migrating rashes for years while I was ill with lyme, that did not improve until I had adequate treatment. It is part of lyme. Read lyme websites.
If you are still having rashes since posting June 7, consider lyme still. DO you have other symptoms that are not completely gone, as fatigue??
I had/have the same thing. I had 3 bullseye rashes at the same time in 1992. I had no idea what the rashes were. Anyway, along with a host of other things I kept breaking out in rashes all over my body for not reason at all. This has continued for 16 years although the rashes are not as frequent. I thought it was an allergic reaction to PCN too. However, I found I broke out in the same bizarre looking rashes for no reason whatsoever.
I had same type of thing which was attributed to an allergic reaction to Amoxicillin.
Mine were Itchy red blotches head to toe which turned into a poison ivy type rash if I scratched it. Research "Hives" reactions and try Benedryl if it gets unbearable.
DG