Did I play this correctly?

[Mathieu]

Here I would check raise the flop. We know that CO will most likely bet this flop even if it did not help him. So when we are ahead, getting a check raise will get more money into the pot and will protect our vulnerable hand by forcing M1 to call 2 cold.

Also, a check raise shows strength, so CO's reaction should give you a better idea of where you stand.