I've been on peritoneal dialysis for two years. I'm now noticing that I'm urinating s lot less than before. Should this be a cause of concern, ?

Loss of urine. This is average, actually, for a person on peritoneal dialysis. Over about 5-8 months, a person receiving hemodialysis loses urine production. A person receiving peritoneal dialysis typically retains urine flow for 1-2 years, sometimes longer. Loss of urine flow diminishes native kidney clearances, so your diet will have to be stricter and your nurse/doctor may have to raise dialysis bags/day.
Yes. Kidneys are dry, or functioning less. See your nephrologist.