[ariadne]

you should build up gradually at first - probably ease back from the pressure you're using - after a week or so you'll be able to use more pressure without risk of blistering or soreness. If you do overpump you'll need to stop for a few days while skin recovers so you cant hurry it.
For uneveness, you need a food bag clip ("clippet?") that you can clamp across one of the tubes and then further pumping will all be directed at the other cup.
x Aria