Depo stopping periods?

So obviously depo is different for everyone when it comes to periods but I’ve been on it before and don’t recall it stopping my period the first three months. I took my shot on August 12th, after being off of it for long enough to get two periods, and the day I took it was the third day of my period and it stopped completely. I was supposed to start my period two days ago but that never happened and I was worried that when my period lasted only two days that I could possibly be pregnant so I took a test on August 14th and then again on August 22nd I believe, a week later. Both tests were negative and I have a UTI that I haven’t been able to go to the doctor for so I’ve been getting cramping for the past month (very dumb idea to not go to the doctor yet, I know) I’m 17, and I’ve told my mom about the pain I’ve been experiencing and that I believe that depo stopped my periods already and she says that although it can happen that it shouldn’t which is probably true. I’m hoping I can schedule a OBGYN appointment soon so I can stop worrying if I’m pregnant or if the shot is the root cause in my most likely missed period I’m going to have. The day before my period was supposed to start I had very bad cramping and very bad back pain but it went away the next day and now I’m having cramping again but I believe it’s because of the untreated UTI or maybe even something worse since it is untreated. Is there any advice someone could give me as to what could be going on and if I should be worried? Although I took depo on my period, it stopped so at first I thought that my period randomly just ended and I had sex 6 days after I got on depo, making myself believe that I basically wasn’t protected immediately like you’re supposed to be because my period wasn’t “normal” when I got on the shot, and the condom broke but he did pull out in time. I’m probably being overly dramatic because I have literally been a anxious wreck since before I even got on depo, it’s gotten so bad that sometimes I can’t even sleep at night because I know if I am in any way possibly pregnant my mom will kick me out and I’ll have no where to go.