Could My Worsening Abdominal Pain And Urinary Symptoms Indicate Something More Serious Than A UTI?

I m unsure if I have a UTI or something more serious. I ve been having lower abdominal discomfort/pressure, with a shooting pain below my navel every so often. I ve also felt like I need to urintate constantly and have some minor pain while doing so. I took home UTI tests 3 times and all came back positive for the leukocyte test but negative for nitrites. This has been going on a few days. I ve made a doctor s appointment but it s taking days for me to get in. At first today I felt like my symptoms had been decreasing but I ve suddenly started feeling worse. Tonight I began experiencing some cramping and pain on the left side of my abdomen as well. I m not sure if the situation is emergent or if I can wait until my doctor s appointment tomorrow. Another reason this has caused me to worry is because I took plan b about 6 weeks ago after my partner s condom fell off during sex. I did have my period as normal about 3 weeks ago and have not had sexual intercourse since. Not sure if it could be related but just in case.