You know mine stuck out all the time too at the start. It really annoyed me cause they were so tender and them rubbing against my clothing was painful. But it went away in time. I think it may have been the stretching that happens when you first nurse. I wonder whether one of my nipples was a bit flat.
Re the white tongue, it could be milk. If you can rub it away with your finger, then it's milk. If not, it's thrush.
For preventing thrush, make sure you change your bra or pads regularly, don't leave wetness next to your nipples. Take your yogurt or probiotics - it can't hurt.