Weight Gain

So I weighed myself this morning after not stepping on the scale for two weeks, realizing I've gained an additional 4 pounds ! This is ridiculous ! Ah ! I don't know what to do ! This is too much for me (don't get me wrong, I love my son and NEVER will regret having him), this weight gain is out of control. I have to admit I've snacking like crazy, and I just won't stop, it has to stop.. it really has to stop ! I've already gained a total of about 18 pounds throughout this pregnancy of 24w5d, how much more will I put on?! I'm going CRAZY.