Michaela, what support network do you have? DH/P? Parents? Good friends? Respite from Social Services/a charity?
First, you need to find a few hours to yourself to recharge your batteries.
Next, work out what strategies you are going to try first to help your son communicate his frustrations. Pick the most urgent issue, and work out how to solve it. It sounds like he has real trouble communicating his needs, so perhaps start there? The aggression will reduce with the frustration so, while it's horrible, tackling that as an individual issue won't solve the long term problem.
Also, don't be afraid to go to your GP and ask for medication for either of you. There are a lot of scare stories about behaviour-modifying drugs, but there is a lot of sound research too. If pills are what's needed to calm him enough to learn to use copign strategies, then that's a positive.
You really do need to get some space from him, though, give yourself a chance to miss him for a couple of hours and you'll go back to him full of energy to help him with (I hope) 