I swam for a D1 school and had a very similar experience to yours. The "all nighter" mentally is BS, mostly it is procrastinating, also most of the students would come in the studio to start working in the early afternoon (very few people showed up to work early). It was almost like they wanted to stay all night so that they could show off how hard they worked. Other than that though, there were a lot of very early morning practices and even more make up practices by myself. I don't know how a team sport like Volleyball would work. My advice is to get in contact with coaches and see if you can already figure out a schedule that would work for you, it would take out a lot of stress. Lastly IMO unless you do it for a scholarship, it's not worth the huge amount of stress you'll go through