What Causes Pre-menstrual Spotting With Persistent Frequent Urination?

In june i spotted light blood a week before my period and i had to always go to the restroom all the time and then i had my regular period for June and still urinating alot. I also took a hpt and it came back negitive. Then in July i still have to go to the bathroom alot i had my period again around the same time i had it in June except i didn t spot a week before in like i did in june, and its August and i still have to pee alot and i been tired alot lately. I started my period today and i have a mild tight feeling in my lower stomach and mild cramping and brownish mix with red blood. I dont think im pregnant because i dont have any other symptoms of pregancy im just curious to know what going on. Ps, it don t hurt when i pee just a tingly feeling sometimes.