Back from hospital...
Drum roll, maestro, please!!
The catheter is out! Gone. Banished. Taken out of my sight.
The relief? Instantaneous.
The hospital transport arrived about 8.15 and we got to UCLH just before 9.30. They saw me straight away in xray dept as a patient hadn't arrived, and the test was a doddle. Instead of inserting another tube, they used the existing catheter to fill my bladder with dyed water, then when I was uncomfortable, had to wee past the catheter.
Everything healed and catheter came out. Phew! Then once I'd emptied my bladder normally I was free to leave, reported back at reception for transport home.
Got home around 12.25. Happy me.