Leaver buster

Hey i was just curious why i got put in a lower priority queue i just came back after about a year or so hiatus and have played four games i finished all of them the only thing is in the last one i didnt click the button to go the the post game lobby and left for awhile i came back and now i have to wait 20 mins before i can attempt to find a game. is what i did against the rules and how long till i can get normal queue times again?