Welcome to Knitting Help!
Do you also work where you have to use a computer all day? That can add to the pain especially for a beginner.
First... What size needles and what yarn weight (worsted, fingering, etc)? What pattern? I agree that knitting too tight can cause unnecessary pain. So you need to match needle size to the gauge unless otherwise called for in a pattern.
Give your hands a break every half hour or so and don't overdo it. Warm water helps as mentioned.
Re: Dishwasher...couldn't live without mine. I have enough dishes so when there is only two of us I only do it twice a week or less. There are 4 of us here for a few months so it's getting run every 2-3 days. In my case I save water by using a short cycle and can wash a lot of dishes. I still have plenty of hand washing every day, too.