Learn to stand in the saddle to relieve you seat pain. Try to get half a minute or better time out of the saddle every five minutes or so.
You should be able to go until you need to stop for a bathroom break. Some of us have regularly gone 25 or 30 miles before the need gets to urgent. With carefull planning the full 60 could be done with out a stop.
Converting your time (just linearly) to a regular marathon race (42.195 km), you would have done that distance in 2 hours 14 minutes 44 seconds. At http://www.unicon14.dk/gb you can find the results lists for the last world championships, including the marathon. There you get some feel for what other folks achieve. Basically your time is not bad, but not very competitive either.
For racing any distance (except very short ones), you should push so much that you cross the finish line exhausted, but not dead. So if weren’t tired, you should have pushed more. This is quite obvious to me, so maybe I misunderstood the question.
I’ve raced a marathon, and done non-race distances up to 80 km. I try to stay hydrated but not drink more than that. So I usually don’t need a peeing stop. For eating and drinking: what Sander said. Don’t stop for it. As to saddle pain, numbness etc: it very much depends on the rider and their tolerance for discomfort. But also on the type of seat and its adjustment. In addition, with training I found I could take longer between breaks. For races up to marathon distance I don’t need a stop anymore, but I used to. Bungeejoe’s suggestion to stand on the pedals is good, although I think his suggested frequency and duration are more than you would need. When standing you can’t maintain full speed, and it is more tiring on the legs. So restrict it to what you really need. All this is for racing, if you’re doing a tour you should be much more relaxed about taking breaks etc.
I assume you were on a (non-geared) 36"? What crank length were you running? Usually going one notch shorter in cranks (e.g. from 140 to 125 mm) gets you some more speed, but it depends on the hilliness of the course. Also, you need some time to get used to shorter cranks, the higher speed may not materialise at once. But since the race is still five weeks, you have time enough.