Teething

[Newmum26]

My LO has his bottom middle two teethe through he is nearly 5 Months Old. He had been showing signs for a few weeks before they sprouted up he was dribbling excessively, cranky at night time, fussing with bottle.
They are through but now about a week later we seem to be starting the whole process again he's showing the same symptoms as before and waking up in pain at night gums red etc. Do the top middle teeth follow than soon after?
I'm aware he is early compared to my friends babies