Urinary Tract Infection cause my period to be late?

So, on August 19 I had sex (I always use a condom) 2 or 3 days later, I had my period. Then about a few weeks later (middle of this month) I had sex again & like I said, I used a condom. I had a UTI the following week. I took antibiotics the doctor prescribed for me for about 5 days & it went away. My period was suppose to come October 23, I believe but it hasn't. I'm very confused, scared & stressed. I took a EPT last week the day my period was suppose to come but it came out to be negative. I have been having cramps, but no period I'm only 16 so it's not like I know very much & I'm scared to talk to my mom cause she's not understanding when it comes to me having sex & she'll most likely suspect I pregnant. I'm not sure if I am or am not though. I mean, the EPT was negative & I used protection, but still. Someone please help.me, IDK what to do