Hello,
I am currently in the process of completing the application to (hopefully) transfer to ND as a sophomore this upcoming fall. I go to a huge state school so developing a close relationship with a prof was not very easy. I fully realize that the responsibility falls on me to go their office hours, etc. Over the past semester, I developed a semi-close relationship with my poli sci professor due to the fact that I was doing the Honors option in his class and I went to him for guidance multiple times and performed very well in his class. When spring semester started, I sent him a really nice email thanking him for his guidance, etc and asked him for a letter of rec as he was the prof I knew the best. It’s been a couple of days and I am having a LOT of anxiety because I have not received a response. In addition, I looked up his schedule and he is not teaching any classes this semester ( he has an independent study no one is enrolled in). My only other option would be to ask my TA from my calculus class bc he knew I was a hardworking student and I did well in the class ,etc (although he doesn’t know me very well so it’s a reach). Basically, I am panicking that I am ruining my chances with a possibly mediocre letter of rec. Does anyone have experience or know if admissions place a lot of importance on the letter of rec?
I would really appreciate anyone’s help 
I have a good GPA so far and well as solid extracurriculars so I really hope I am not screwing myself over with the letter of rec.