Hi there - I have split your post from the topic that you originally posted on, as that thread was nearly three years old and this way you will get more viewers.
You are absolutely not overfeeding if he's draining the bottle and not getting sick.
You're doing really well!! A lot better than we were when Colin was that little. It's normal to have some irregularities in sleep at such a young age. He still has a lot to learn in general but especially about sleep. Babies work on organizing their daytime sleep first from 0 - 3 mo and then move on to night sleep from 3 - 6 mo.