Fun fact, normal games have a Hidden MMR system so you can still get placed with similar skill people if you play it enough.

How do I check my MMR?

There is no official way to check your MMR. However, you can partially figure it out from how LP points are distributed after the end of a ranked game. The easier way to see your MMR is to use a service that pulls data from the API.

Why do you lose LP for dodging?

A League Points penalty is applied to the player who dodges, -3 points for the first time and -10 for the second time before the timer reset. This penalty cannot make a player drop ranks but will stack in negative numbers. This is capped at -100 LP.