Hi Ehrris!

What the doctors basically told you is that you are susceptible to gout; a condition where uric acid crystals form in the joints causing pain and inflammation. Did the doctor also check your uric acid levels at the time you saw him? It's a shame that they didn't tell you that by avoiding those protein sources highest in purines (which contribute to the uric acid buildup), you could have continued to low carb with a lot less trouble.
This link may help you avoid further problems if you avoid or limit the foods listed that are highest in purines.