Yeah I agree with the others - wow that's a hectic load but you know what? Your positive attitude stands you in great stead - you've got your witts about you, you are determined and you strike me as someone who will stop at nothing to achieve your goals. All very positive.
The reality is, this is going to be somewhat stressful, but "mentally" planning for it ahead, might help somewhat, because unless you can drop one activity, and it doesn't seem like you can, having action plans in place will work.
Even something as simple as a Weekly Calendar, with days of the week where you jot down your commitments - and it's vital that you leave some "me" time that you have to yourself so you're not overwhealmed with your other activities. You need this time to recharge your batteries, or so to speak.
Good luck with this - you're a fighting winner