I lied and I feel horrible (long read fyi)

So I was able to visit home over the weekend and during that time I got to see my boyfriend. We had sex once before I Ieft but the night after I immediately got UTI symptoms. I told my Mom I was having constant urges to pee and she immediately assumed it was because I hadn't drank much water and was dehydrated. I flew back to school the next morning and today being the day after, I'm now getting intense lower back pain which is a sign of the bacteria reaching the kidneys. When I told my mom this she started freaking out even more since kidney infections could get very serious. At the end of our last phone call she asked me for the first time ever a sex-related question, and directly asked if I had sex with my bf while I was home for the weekend. I lied to her saying why would she even ask that question and telling her it was because I was dehydrated. I lied because my Mom is very Christian and I just couldn't break her heart knowing her daughter was in a sexual relationship, even though I'm 21 and old enough to make personal decisions such as this. But after lying to my Mom I just feel absolutely awful. Although I am on my own search for God I know that having sex is a constant mental fight of wanting to do it and yet telling myself I shouldn't. But in the end my desire always wins. I texted with my bf right after my call with my Mom and told him how I didn't know my boundaries at the start of our relationship and how I was sorry for pushing him to have sex during times he didn't particularly feel like it (I know I'm awful). Our sexual relationship started pretty badly since I really wasn't ready but did it anyways (I thought I would be smart enough in these situations but clearly I was not). Yet after our first time having sex I constantly crave it, especially since we have been long distance from the start. I told my bf just now that I didn't want to have sex anymore and he agreed to it right away. I guess in the end I really feel like I got what I deserved for lying to my Mom and also just being an emotional mess about wanting yet also not wanting sex. 💔