The theory behind incontinence being worse if you get tired is fairly straightforward. As part of the op, they removed the prostate with that section of urethra and one or both urinary valves that control continence. They also cut through the main muscles controlling the bladder sphincter. Then they joined the two cut ends of urethra back together, often needing to replace the valve and stitch it in place. Your brain then has to relearn how to control the sphincter and valve, much as you did as a toddler being toilet-trained - like a small child you have to concentrate to do that and if you get tired or start to concentrate on something else, the bladder control goes on the back burner (young children often get engrossed in playing something and then have accidents because they forget to hold on)
The small amounts of blood can be from where the two ends of the urethra have been cut and restitched, or from where the valve has been re-sited (if that was done). Clots are normal as the area heals but if there is more than a little blood it may be down to having pulled the join or from other damage and needs checking out.
When John had open RP he was told (and all the paperwork / information leaflets said) that he would need 12 weeks off work. in the event, he was working from home around 9 - 10 weeks post-op but his car insurer wouldn't clear him to drive until he had seen the surgeon at 12 weeks.