A visit to the urologist should help. A cystoscopy should be contemplated. Your problem can be Overactive bladder (OAB), which is a condition caused by sudden involuntary contraction (overactivity) of the bladder detrusor muscles. OAB is characterized as urinary urgency, with or without urge incontinence, increased frequency and night time urination (nocturia), in the absence of any causative infection or any bladder pathological conditions. The cardinal symptoms of OAB are considered to be urgency, frequency, and nocturia. In fact, urgency has been found to be significantly related to patients' quality of life. The investigations to establish the cause are;
1) urine culture for mycobacterium; this will need special culture medium
3) vaginal ultrasound
4) frequency / volume charts
5) urine cytology
7) postvoid residual volume assessment using urethral catheterization or ultrasonography
8) cystometry: This is a simple method for testing the bladder's storage function and provides information on bladder capacity, the extent of accommodation or compliance, the ability to sense bladder filling and temperature, and the presence of an appropriate detrusor muscle contraction.
9) urodynamics: This is used to measure bladder pressure during micturition.
10) uroflometry; The urine flow rates are assessed based on the detrusor pressure and urethral resistance. One voids in a commode connected to a computer which measures peak urine flow rate, etc.
Your last three tests have been done before but should be repeated, if done more than a year ago.
Treatment of overactive bladder is by following;
1) Anticholinergic medications like Oxybutynin and tolterodine.
2) Capsaicin: bladder (intravesical) administration in OAB.
The other possibility to consider would be Interstitial cystitis. The cause of interstitial cystitis is not very clear. It is though that bladder muscles or the nerves in the bladder or the central nervous system become too sensitive and this causes the increased frequency or the pain. The internal lining of the bladder in IC changes and this change can be primarily responsible for the symptoms or the change is secondary to other problems like Antiproliferative factor (APF), which changes the bladder. An endoscopy can diagnose it. Following measures can help in interstitial cystitis and overactive bladder syndrome;
Following is the comprehensive treatment protocol;
1) Medications; Gabapentin, hydroxyzine, montelukast
2) Physical therapy; Pelvic floor physical therapy (PT) may be recommended to decrease tightness in these muscles. PT can decrease bladder or pelvic pain as well as urinary urgency and frequency. Physical therapist works on the patient's body to manually "release" the tightness, tender points, trigger points, and restricted movement of the connective tissues and muscles.
3) Exercises; Many patients feel that gentle stretching exercises help relieve symptoms.
4) Electrical stimulation; sacral nerve stimulation.
5) Behavioral therapies; Behavioral therapies for urinary frequency work to slowly increase the time interval between voids, which increases the amount of urine the bladder can comfortably hold; this is called timed voiding.
6) Diet; alcohol, tomatoes, spices, chocolate, caffeinated and citrus beverages, and high-acid foods may contribute to bladder irritation and inflammation. Artificial sweeteners may aggravate the symptoms.
Please read this resource for the overactive bladder syndrome;
Please feel free for your follow up questions.