Magnesium and the B Complex Vitamins are essential to properly handling stress. You ought to also look online for a really absorbable, high nutrient, multi-vitamin & multi-mineral, supplement. I'd go for what has a lot of good reviews.
Magnesium is essential to handling stress, and stress depletes magnesium stores. No wonder you feel worse with stress.
Here is further information on magnesium and bladder urgency:
http://www.medhelp.org/posts/Urology/Magnesium-For-Bladder-Urgency/show/1336084?personal_page_id=1012978#post_6106528
FANTASTIC information below:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2146789/pdf/canfamphys00077-0094.pdf
http://www.medhelp.org/posts/Neurology/Muscle-Twitches-All-OVER/show/295459
"Magnesium: The Stress Reliever" by Leo Galland M.D., F.A.C.N. (online article)
"The Importance of Magnesium to Human Nutrition" by Michael Schachter M.D., F.A.C.A.M (online article)
"Magnificent Magnesium" by Priscilla Slagle M.D.
http://www.thewayup.com/newsletters/081501.htm
"Magnesium also helps regulate nerve cell function. It must be present in adequate amounts in the synaptic gap between nerve cells to control the rate of neuron firing. (3) When synaptic magnesium levels are too low, nerves fire too easily from even minor stimuli. For example, noises will sound excessively loud, lights will seem too bright, emotional reactions will be exaggerated, and the brain will be too stimulated to sleep. In extreme magnesium-synaptic deficiency, epilepsy--a sort of whole-brain shotgun-blast excessive neuronal firing--may result."
Source: The Underappreciated Mineral of Life Part I
By James South M.A.
Blessings. :)