I removed a switch from the wall(re-model) and replaced it with an outlet and added 4 more outlets plus a switch-leg up to a new ceiling fan. The power to the old switch is old braided 12-3 with no ground I am not able to run new wire back to the panel. I did run a ground wire from that point to a newer outlet that does have a ground wire back to the panel. I also started with GFI receptical at that point. I continued to wire the other 3 outlets with 12-2 , the from the last outlet power up to the switch with 14-2 followed with 14-3 up to the fan. This circuit is on a 20amp breaker and has 7 outlets and 2 fans. Is it OK to leave it on the 20amp , or should I switch it to a 15amp breaker?

Now that you have #14 wire mixed in the circuit, the breaker needs to be a 15 amp.