@BLTLover, times are hard, really hard.
It’s all been going on for sooooo long.
Great that you are doing the course & following through with your plans. However, lockdown (& the many varying restrictions) have thrown a malevolent monster spanner in the best laid plans. So please be kind to yourself & flex yr expectations a bit.
OLD - maybe park this extracurricular fun until you have settled into a better routine.
Sleep - after caring for your precious child, this is your number one priority because your overall equilibrium is built upon this. It is is false economy to deprive yourself of sleep.
Settling into Sertraline takes time. If you are sleeping heavily, it may well be because you need to sleep after a extended period of not sleeping well. Providing you can get up in time for you child & then work, can you have accept your need for extra sleep for a while. Can you take the meds earlier in the day/evening so you can clock the extra deep sleep cycles by the time you need to wake in the morning? Don’t hesitate to let your GP know how you are getting on with the meds, sometimes it takes missing a few prescription frogs(!) to find the meds that work best for you.
Dawdle a while with the course work until you have sleep & meds ticking over nicely.
BTW, the OU stinks but it’s not you.