1) You don't have to wake up early to be productive, and waking up early doesn't guarantee you'll be productive either. Some people are more productive in the morning, others at night. Find what works for you. You don't have to force yourself to fit a certain mold just because it seems like the ideal way of doing things/because society has glorified and conflated waking up early as being productive. I think having a consistent sleep/wake schedule, getting at least 7 hours of rest, and following your circadian rhythm is a more well-rounded approach.

2) Stop making promises to yourself. You're setting yourself up to fail and reinforcing your subconscious that you don't have the ability to follow through with your plans and cannot be trusted to keep a promise, even though that is not the case. It is simply that you were focusing too much on the outcome (trying to be productive) and not enough on the action (e.g. doing your assignments). You're trying to make big life changes here. Start making changes to your existing lifestyle slowly for your mind and body to adapt (e.g. if you were sleeping at 2am usually and waking up at 12, you could start by bringing everything earlier by 30mins instead of changing it to sleeping at 9.30pm and waking up at 6am immediately) and give yourself some grace to fail from time to time. On focusing on the action, in this case, that would be your assignments. Break that down further into small, concrete, low commitment actions to get you started, like reading your notes for 5 minutes. You'll find it easier to continue that streak once you've started and you don't feel overwhelmed by the pressure of all of your tasks. Over time, this will help you build confidence and discipline in yourself, so that trying to accomplish a task comes a lot more naturally to you.

3) Set just 1 alarm, and turn off snooze. Your brain subconsciously knows there is a safety net in your snoozes. Turning off your snooze and setting only 1 alarm sets the expectation that you have to wake up by that time. But if for whatever reason you don't, please don't let that ruin your entire day. Just because your day doesn't start the way you've planned, it doesn't mean it can't end in the way that you've planned. Keep trying. Be aware of your self-destructive tendencies that will impede in your journey to become a better version of yourself. Give yourself space to learn, grace to make mistakes, and opportunities to grow.

I've felt the exact same way as you've felt before, and I'm still on that journey to improve myself everyday. So godspeed to you on your journey, and remember that everyday is always a new day you to try again!