Hello and welcome to HCM.
Thank you for your query.
First of all, there are many causes for UTI-like symptoms or even for a UTI. Sometimes it is just a plain and simple UTI, but other times a well-experienced doctor would look into other causes for the same. As you visited a female doctor, a physical examination of the genitals would have been appropriate. You can request for the same, as the doctor will be able to diagnose the cause for your presentation more precisely.
In the meantime, some of the most common causes for sores inside the vagina and swelling of the genitalia are:
yeast infections,
genital herpes,
candidiasis,
bartholin gland cysts, etc.
Although itching and burning sensation are considered UTI symptoms, they are also commonly seen along with sexually transmitted infections. Do visit your doctor at the earliest, preferably a gynecologist or a sexually transmitted diseases specialist. In the meantime, please keep track of all developments, and if there is a discharge, please observe the color, consistency, odour, etc.
I hope I have succeeded in providing the information you were looking for. Please feel free to write back to me for any further clarifications. I would gladly help you.
Best wishes.