You should always seek a second opinion if your judgement indcates that. The one variable that would indicate that her condition might not be pollakiuria (which, as you already know, does not warrant any particular worry or alarm) is the length of time it has persisted. Generally, though your daughter may be an exception, the condition does not persist for as long as six months. Has the medication been helpful, or have you not wanted to start her on it? Aparently the doctor thought you were referring to polyuria, which refers to the passing of a large volume of urine within a specified time period. With your daughter, the issue is not so much the volume, from what you indicate, but the frequency of urination. It doesn't sound like the doctor understood what you were talking about. But definitely seek a second opinion, preferably from a pediatric urologist.
Is she overall very petite person--just wondering because her weight is on the light side for a girl her age--my little guy is 3 and he weighs 36 lbs and is in the 50% tile for weight and height....maybe it is a metablism thing where things are just going though her and the wieght height and everything is a contributing factor--does she actually pee all the time or just feels the need and doesn't go--I have no real insight to this other than maybe taking her to a urologist who specializes in these disorders versus the peditrician...Good Luck and hope you can find her some help