DS is 7.5 months old, first two teeth came through at 6 months, not too much trouble, he was off his food for a day. Two top teeth are now looking like they are coming and he is a different baby. He wants to bf constantly, and is very sleepy and grumpy. When he goes to sleep he wakes up after 20 minutes crying and has been awake from 2am the last two nights. He has a bit of temperature but calpol brings it down. I guess it is the sleeping more that makes me worry. Is this normal? How long do teeth take to come through?