sudden change in sleep

My baby boy is 13 and half weeks now but a week ago suddenly stopped sleeping through the night and i'm not sure what i should be doing with him at night. He started sleeping through at 2 months old, from around 8pm-5am. He would wake but re-settle himself about twice (that i heard). For the past week though, he has been waking (only once at the moment) and not going back to sleep so i get him up and feed him (although he doesnt always seem to want it) but he's not going right back to sleep and its taking an hour or so of sitting in the rocking chair before he drifts off. Should i leave him unless he cries? or should i be putting him to bed awake, only thing is i dont think i can do the cry it out method yet. he has been being fed to sleep, although lately he has hardly drunk before he drops off and last night he didnt want the breast at all and fell asleep while being rocked by my OH in the rocking chair. he has a little dry cough and his poo has been green for past week or so and i am wondering if he has teeth moving around as he has some symptoms of teething so could it be that's he seeking comfort - in any case what should i be doing during the night so that we do not start bad habits??

I've been going through a very similar thing with my baby boy also whom is 13 weeks 5 days - the last 5 days, he has been waking about 2-4 times during the night, where is ever since about 8 weeks he would wake only once. Everything you wrote in your 1st email is exactly what has been happening with my son... how weird?!

I too have been wondering if he may be teething as he always shoves his fist into his mouth to suck on it, is dribbling a lot and his cheeks got really rosey on two occasions. I got my mum to have a look and see if she could see anything in his mouth but she didn't see any little buds. I feel sleep deprived and wondering what is going on with my little boy. He use to be a dream baby when it came to sleep and settle himself so easily when I would put him to bed, but now he cries the house down - tonight it took us 2 hours to settle him to bed after I had 1st put him down!

I hope things have gotten better for you - I'm hoping its just a phase and that he snaps out of it soon, as this lack of sleep is pretty hard.