My son is very active & soon will be 5 month old. The prob is that he is not feeding milk properly since 4 days. Due to extreme summer days we also started feeding drops of water boiled with a bit of saunf, salt & sugar. Is that causing issue? Also he started sucking his fingers thumb too much since 1 month, is that something causing stomach problem? As we are unable to understand why he is not feeding properly now.