How are you going emotionally? You've had a really tough few weeks and have a right to be out of sorts. Kids are very sensitive and if you're feeling sad or short tempered that can manifest itself in other behaviors. When my dd was the age of your ds I went through a stressful time (nothing like yours) but I was short tempered and generally grumpy, and it lead to much more challenging behaviour. Once everything had calmed down, dd went back to her usual self.

I would give it time and try and maintain your normal routines and boundaries. I also find at these times you need to hold them closer for further reassurance, so I would encourage some cosleeping if he wants it, and stay longer at day care if that helps, and generally lots of cuddle time together (bath together, watching DVDs, some carrying around at times etc).

I think you'll find it all settles down in a few weeks.

Good luck!