It's really hard to explain just how little time you have to do things when you're older... until you live it, it seems impossible. I currently work from home with my own business, with hours I set, have 1 kid, and sleep 5 hours a day and I definitely don't have time for 4 birds.
I never only got out of class at 3 during college. Somedays I left my dorm at 8am and didn't get back until 6pm. I then worked parttime at the dorm for 20 hours a week, usually overnights. I would not have had time for one bird.
My professors told me that for a 3 credit course, to count on at least 2 hours of homework or studying for every hour of class I had. For 15 credits that could translate to 30 hours of classtime and 30 to 60 hours of homework a week.
Then what about after college? You get a fulltime job, 40 hours a week minimum, add in sleeping, grocery shopping, house cleaning, any social activities...
it all dwindles very quickly.
Of course it is not impossible. But "a lot of time now" is not a good indicator for how much time you will have later.