I do the same thing. I work all day and then train at night. Don’t look at being crushed on the bottom as a negative. I am a blue belt and it still happens to me, sometimes even by white belts. Practice your defence, escapes and surviving which is a big part of bjj. Also look for small victories, like surviving 30 seconds before tapping instead of 15 seconds, blocking one sweep attempt, passing a guard once during a roll, escaping side control once during a roll, etc. These seem like little things but it’s definitely signs that you are getting better. Also talk to your professor and ask if he has suggestions on what you should work on or notices anything you should work on correcting. It’s hard, especially at the beginning, but stick with it. Things will start making sense at some point (for me that was probably about 7-8 months in) and that’s when it will really start getting fun and addictive.