Hello Bill and welcome to HCM.
Your concern is understandable. As an
Urologist, i must advise you, to see a doctor in the casualty / ER of the hospital, if pain is very severe.
If the bladder mass is diagnosed after doing an Ultrasound/
CT scan, then you will need treatment, to remove the mass.
Bladder mass, depending on location, can give rise to difficulty in passing urine and pain, like you're describing.
Your symptoms can be relieved by analgesics and medicines to improve the urine flow, which the doctor will prescribe, till surgery.
Wish you a speedy recovery.