Those are herx symptoms, so that means it's killing the bacteria.
Instead of backing down the dose, you need to either start or increase your detoxing. There are many good detoxing ideas in the "New to Lyme?" thread and on here: www.tiredoflyme.com/detox-methods.html
Watch the stomach bloating though - although that's a symptom of Lyme and Bartonella, it is also a sign of yeast/fungal issues. You should make yourself aware of the symptoms of those issues and either be sure you are on a really good probiotic or get on one to help lower the risk of having yeast/fungal issues to deal with on top of these infections.
There is a very excellent post about
Yeast/fungal issues on the bottom of page 2 of our "New to Lyme?" thread by Pirouette. I would encourage you to read through it as well.