Blood in urine and painful pee

Hi, was wondering if anyone could help, I had the LLETZ yesterday and the doctor said it went well, felt fine no pain, no vagina bleeding, this afternoon I started experiencing an urgency to pee, and when I went it was painful, the more I went then I noticed blood on the loo roll, called my gp did a urine sample, it was confirmed I could have a UTI but the result was inconclusive, any idea what this could be or if anyone has experienced this? Have taken my first antibiotic (as prescribed by the GP) and the urgency has gone but there is still bright red blood on the loo roll!