As-salamu alaykum everyone, I need advice on strengthening my iman.

I'm really struggling and feel my iman is getting lower each day. I returned from Umrah about two weeks ago, and honestly, I thought the journey would make me a better Muslim, but instead, I feel like I'm slipping. Since coming back, my sleep is all over the place-I'm up until 4 AM, wake for Fajr, and then sleep way too late into the afternoon. I've been dealing with depression and ADHD, which makes even simple tasks take forever, and it's really hurting my spiritual state. Before Umrah, I used to pray on time, but now I find myself rushing through Salah right before Maghrib. I keep putting off Salah at-Tawbah for repentance, and after Maghrib, I barely manage to pray 'Isha at the very last minute, do some dhikr, recite a few surahs, and make dua, which still feels like a huge effort. Every day I promise myself I'll improve, but it just gets harder. Why do I feel this way after such a blessed journey? Allah invited me to His house, and now I can't even do the basics-it makes me feel like a hypocrite. I know it's probably my nafs acting up, and that everyone has their highs and lows, but how can I turn this around before Ramadan ends? I'm scared of leaving this holy month without being forgiven because I'm not doing enough. Any advice would mean the world, jazakum Allahu khayran.