I also work 33 hours a week.
Now, I know sleep is very important (improves health, boosts recovery, helps solidify studying, etc), so I like to sleep 7-8 hours every night. I'll say 8 because usually it's takes me 30ish minutes to fall asleep. 8x7=56.
Let's add in workouts! Each workout takes about 1 hour. I workout 3 days a week, plus 10 minutes of mobility everyday. (I'll say 6 days a week for simplicity). Total fitness work: 4 hours of my week.
I also try to fit in 30 minutes of Bible time a day. (I'll do 6 days a week for simplicity and because I usually miss one a week anyway), so 3 hours a week.
I have some chores as well, but they usually intermixed with eating, so I'll combine these... I'd guess about 2-3 hours a day. I'll multiply but 2.5 as any average, and take round up because I eat a lot(3750-4500 calories a day): 2.5x7=17.5=18.
I also try to have friends, but time with them varies and most of it is spent on Sundays, so won't factor that in. I also like to spend a little time researching fitness stuff, to improve my knowlegde and skill, but that varies as well.
I like to take the Lord's day off of studying and working out, so that makes me have to cram more in my week days.
Last thing: driving: I drive about 45 minutes a day. Everyday. 0.75x7=5 (rounded down).
Now let's add it all together!
21+33+56+4+3+18+5=140. That's about 20 hours a day, 135/7=20. 24h-20=4 extra hours.
Now, let's factor in Sunday. 140-(8 hours of sleep+30 minutes of bible time+2.5 hours of eating/chores+0.75 hours of driving)= 128.25 hours. 128.25/6=21.4 (rounded). 24h-21.4h=2.6 extra hours.
You see, the point of this is not to brag how I'm so busy and you all should feel lame for not being busy. I actually have 2.6 hours of time I could waste, or spend productively on projects or spend on self maintenance, or prayer/relaxation or just talking with friends... everyday, not including Sundays. That's about 15.5 hours a week (not including Sunday).
Holy cow, what could you do with 15 hours of free time? A lot, right? What I'm trying to say is, even if you 're really busy, you probably have time do what you want to do. Just rid yourself of time drainers (aka: Facebook, YouTube, TV, etc)... Or limit them, a lot. I still have over 15 hours of theoretical 'free time', while I workout more than the average person, leave Sunday aside for friends and God, work a lot, sleep a lot, study a lot and eat a lot.
So, what is your excuse? Why can't you workout? Why can't your read your Bible? Why can't you eat enough? Why can't you sleep enough? Why can't you study enough? It probably is not because you are too busy. You just waste your time on nonsense things. I know I do, and my grades have suffered from it... but I am still maintaining a B, because I revamped my studying and my priorities before I fell into a unsadisifying and depressing grade of C or below.
You're busy, but you got time.