You're not alone, but you are exhausted!
A few hints - a 9 month old does not wake up because he is hungry. He does not need to eat. He will make up for it during the day, really he will. Ask the doctor. Yes, fill him up if you can, but he's requiring WAY too much of you to get back to sleep. Two hours? Not good for either of you!
At this age, he needs his rest. That's absolutely essential for brain development, so if you have to do a couple of tough nights to get there, that's what you do. And, frankly, you are sleep deprived as well - you're not only miserable, you are a risk if you are driving (to yourself, to him, to others).
It's not the teething. It's gone on for too long for that. It's bad habits. He's relying on YOU to comfort him or he's relying on pure exhaustion to fall asleep. Neither one is good. We see it on Mamapedia and in the world at large in many forms - co-sleeping, nursing of older infants and toddlers, and so on. I support all of those if they are what the family wants - but not to the detriment of brain functioning.
Please look up or talk to your doctor about self-soothing, and about the Ferber method. It's not a cruel and wanton "cry your lungs out forever and feel terrible while I ignore you" method at all! It's a "you can do it" method of calming and soothing, letting him know he is safe and competent to fall asleep. It builds confidence and self-reliance - and yes, they need this at 9 months old! You don't pick him up or sing lullabies or walk around the house or feed (not even water) - you pat on the back, you say "You're fine, time for sleep" and you leave. You go back in 10 minutes the first time, 20 minutes the second, 35 minutes the third, and so on. You DO divide with Dad or Grandma or anyone else available, but everyone follows EXACTLY the same script! You have 3 nights of absolute hell, and then you are DONE!
Please, please, see this as a necessary stage for his development and his growth, and not just as a means to have YOU sleep more. It's like carseats/seatbelts, toothbrushing, and not running into the traffic - doesn't matter if someone likes it, it's essential. And it does become automatic.
I went through this, hated it, but listened to the pediatrician, and we were all so much better off!!!