I researched under glucose levels in urine and diabetes because my is a severe diabetic and glucose in the urine is sometimes one of the symptoms. This is what I found below and I cut and pasted. It does mention kidney damage as another factor. Please get retested to see if there is blood really in your urine.
2. Can I test my urine glucose instead of my blood?
Not in most cases. Glucose will usually only show up in the urine if it is at sufficiently high levels in the blood so that the body is "dumping" the excess into the urine, or if there is some degree of kidney damage and the glucose is leaking out into the urine. Urine glucose, however, is sometimes used as a rough indicator of high glucose levels and the urine indicator strip (dipstick) that measures the glucose is occasionally useful for tracking the presence of protein and ketones in the urine.
I have had a test done because I knew I had a UTI and it came back negative. I would suggest to have them do another test because just like Pregnancy tests they can mess them up. You never know what kind of person you have working on your tests. They could have gotten A's in school or just passed by the skin of their teeth. Always remember that and ask lots of questions. Good luck!!!
Sorry if the above response didn't really answer the pregnancy question. I just wanted you to know that you shouldn't let a UTI go for a long time if you think you have one. On a pregnancy note, I hope it all turns out for the best for you.