Gout Pal Interactive

I recently had surgery to remove a large uric acid kidney stone. I am taking potassium citrate and since the surgery (June 18). I am have been taking allopurinol since June 25 (3 days).  The doctor said I should check my urine with pH strips.  Before I started the purinol, my urine was about 7.5.  Now, since the purinol, it is 5.0.  I have been eating to promote alkalinity.  What am I missing here?  Shouldn't my urine pH be higher? Any help is welcome.

I'm embarrassed about that last email–I must not have proofread!  Anyway, I drink Tang, add 1/2 of a fresh lemon to a  large glass of water (and I have about 100 ounces of water per day), I add sundried tomatoes to any recipe I can, I eat fresh tomatoes and cucumbers, have only 2-3 ounces of meat per day, fresh green peppers, low fat cheese (2 ounces a day), and nonfat cottage cheese.  The idea, of course, is to prevent the formation of a new stone.  I can't decide how worried to be, though, because this one took about 40 years to form.  I have had pain in the right kidney for many years, but the doctors couldn't find a reason for it, so according to them nothing was wrong!!  These stones don't show up on x-ray.  Who knew??!  I appreciate your response and have found your website very helpful.  Thanks