Erica, I'm no expert but you shouldn't need a lot of pressure during sharpening. Some real experts here have said that they exert around 1 to 2 Lbs of pressure most of the time, and less & less pressure as they finish on a particular stone and do a few stropping strokes to help deburr the edge. You need to let the stone do the work. If you are pushing hard, it will be hard to maintain consistency in your angle and you'll fatigue much too quickly.
Maybe Jason B., Ken, Shaun, or Adam et al. can weigh in here on their technique.
The 1K and 4K Glass stones are great stones, but they are very hard and definitely reward consistent and exact technique and punish the opposite. It is my opinion that if you can create really nice, correctly ground edges on the Shaptons, you can sharpen well on anything.
Once you get quite good at sharpening you should be able to knock out great edges on your knives pretty quickly - most definitely not all day