Thrush is hard to diagnose and difficult to treat as well. It presents itself as nonspecific symptoms that could be anything. One of two signs typically occur first.
Sore nipples occur most of the time with thrush.
It may not be very bad pain but it will exist nonetheless. You may think your baby hasn't been latching on correctly or lazily pulling off the nipple without breaking suction first. It is hard to know for sure if it is thrush. One thing to consider, is if the pain comes and goes or if it persists. Thrush nipple pain usually hurts every single time your baby nurses, though it will feel better the longer your baby is latched on.