First off, let me say that I'm not a doctor.
Secondly, blood in the urine is called Hematuria. If that's not what your doctor referred to it as, then he might be using a medical term I'm not familiar with.
If your doctor did a urinalysis, I would assume infection would have been present if you had a UTI (urinary tract infection). The reason I mention this, is because you said it burns when you urinate from time to time.
If I were you, I'd go and see a Urologist and tell him exactly what you've said here.
The doctor must have mentioned hematuria which causes blood in urine. Hello,
Several conditions can cause hematuria (blood in urine) and most of them are not serious; but because hematuria may be the result of a tumor or other serious problem, a doctor should be consulted.
Causes can be divided according to the affected organ and they are Kidney conditions (infection, pyelonephritis, kidney stones, polycystic kidney disease), Bladder conditions (cystitis, bladder polyp, bladder tumor), Urethral conditions (Sexually transmitted diseases, urethral injury, vaginal inflammation), and certain bleeding disorders.
Diagnostic tests that may be performed include Urinalysis, Urine culture, X-rays of the kidneys, Cystoscopy, IVP, Abdominal ultrasound and CT scan of the abdomen.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.