reoccurring utis

I just found out I'm pregnant so I'm approximately 6 weeks and don't have my first appointment for about 2 more weeks. I noticed an urgency to urinate so called my doctor explaining that I had a uti. I knew it was this because I am prone to them and recognized the feeling immediately. She prescribed me antibiotics and it was cleared up in the next two days. I finished my meds and only about 3 days off them I noticed today I have my uti back. I'm trying my best to drink cranberry juice and stay hydrated but does anyone have any advice for keeping uti's at bay? Im wondering if a consistent uti problem is common during pregnancy and if this is going to be a reoccurring issue the next 8 months? The urgency is bad enough that it's woken me out of my sleep and I can't call my doctor until tomorrow. Help!