Help!

So my son is currently turning 27 weeks this Thursday but for the last few nights he has been having horrible sleep!! The couple weeks before he was doing great at least giving me one 4-6 hour stretch which is great considering he used to wake up every 3 hours for a really long time.. But the last few nights I'm not sure if it's teething or something else he wakes up every hour.. Then last night he woke up 11 times from 10:30-2:30!! I gave in and brought him to bed with me so that I could breast feed him when he woke up because I was just so exhausted/still exhausted.. He's also been more fussy than usual and what seems to me as more aggressive?.. Not sure what to think of it... So tired not sure what to do.. Any thoughts?!