What Causes Recurring UTI And Vaginal Infections?

Hi, a couple of days ago it hurt a lot after i finished peeing. Me and my mom went to the doctor, I got antibiotics and I took them for 3 days as the doctor said. While I was taking the antibiotics my vagina was itching. I discovered that the area around my clitoris was swollen. I have had a yeast infection before but this was milder, and I haven't had 'cheezy' discharge. I've used canasten cream. But will it make my 'yeast infection' go away? The UTI came right back after I stopped taking the anitbiotics, and i'm going to the doctors tomorrow. Why is this happening and do I have a yeast infection?