I too give extra correction bolus for levels over 12.0. I normally add at least half the recommended dosage on again, sometimes I double it! However, that is because I been on a pump a long while now and know my reactions to corrections over levels of 12.0.
You should see a drop starting to happen within 1.5-2 hrs. You do not want to see a drop to target levels within that time as then you are very likely to go low. With pumps the ideal is to get back to target levels at 5 hours.
I do hourly tests if I have had **** with a set. I still go to bed but set alarms on pump to go off every 2 hours then.
Does the new set feel comfy when you aren't bolusing? I never feel a bolus, if I did I would change the set, however I'm not sure what sets you are using. On stainless steel sets that you put in yourself really easily, you pretty much will learn that if it feels odd when going in, then it won't work. My motto is "if it hurts it won't work.
I hope you start to see a drop in levels...**** feeling at 20's....