Tired

Honestly, I've been spoiled with having a good sleeper for the first 7 months of his life, so my current situation in retrospect probably could be a lot worse.   But I am beginning to wonder when its going to end.  It seems that the little one has decided not to sleep a good 6-8 hour stretch anymore with a 4ish  hour stretch to follow and instead is screaming every 1-3 hours at night instead.  The only way I have found to get him back to sleep is by nursing.  While usually I can sleep thru the nursing, I can't seem to do that anymore it hurts much more because of the teeth.
So my first intuition is to blame it on the darn teeth, but there are a lot of other factors that have been added or changed.  First, I am much more stressed these days, I have 2 weeks till my PhD defense and I wonder if he is feeling the extra stress that I am carrying.  Next, he started crawling, but he really wants to walk, and I think partly is frustrated with this. He can furniture walk, but not on his own yet.  And its turned cold.  So we can't spend all day outside, which is something that he loves to do.  So, with cutting teeth, (2 are here finally!) and all these other changes we have a rough sleeper.  So I am just wondering if you have any advice.  Since this is my first, I am in the dark with experience here.
I am not into letting a child cry it out, it just doesn't seem right to me, but any other advice would be great. Thanks.