Sorry Jennay, posted that without reading your post.
I don't really know what you do aged 2 as the sleep pattern is probably better defined by then. Re the waking in the night I would really ignore that for a few nights, get your dh earplugs if he can't bear it!
Re the vomiting, do you have a very calm and ordered bedtime routine eg bath, play, story, milk, teeth, cuddles, bed, give favorite toy, maybe put on some soothing music, lights out and don't go back in! If you follow this routine for a while, and say to him "now you must go to sleep, mummy is going downstairs now" and try the cc then ie go in after 10 mins, then 15, then 20 etc. If he vomits clear it up and put him back to bed calmly after a cuddle, give him toy and follow routine again.
I have no scientific basis for this, it's just what I would do!