the best thing to do is play on his strengths and not his weaknesses ... if cleaning is something he is incapable of doing but he doesnt mind doing the food shopping, then ask him to do this instead.
as for the stress with university, it will always be there - teachers dont treat students with children differently ... however make sure you communicate with people in the class often, that way when youre really stressed, just take a day off - let everything go and just play with your son and have fun. then ask them to send you their notes for class that day. because it is pointless to try and study when youre stressed. if you just recharge for one day you will have the power to keep going again, and study a lot better and efficiently the next days.
as for organisation, one thing i do which really helps me is to spend one hour in the evening when the baby is in bed to set everything up for the next day - i already prepare the coffee machine, do all the dishes, clean the bottles, put all the baby bath stuff ready etc. with your son in bed and the father at work it will get cleaned in no time. then in the morning when you wake up, its not hectic and stressful.
try to focus on whats important, which is university and your son - its ok if the 'big chores' like cleaning the bathroom, hoovering etc. are left for one or two more days and if you spend that one hour in the evening organising everything the daily chores wont pile up.
when it gets too much, what helps me and are a few stress relievers which are great for your son too: i put in headphones and go for a long, long walk with the stroller. or i put my son in his laychair, put on music and just excercise at home, which he finds hilarious. and nothing is greater than dropping everything for an hour and just to have fun.
keep in mind: a happy mummy makes a happy baby
its very tough, but youre doing a great job! keep going and stay strong!