Ever growing belly

My belly will not.stop.growing. Yes, I know I'm pregnant, yes I know that is supposed to happen. But I'm only 28 weeks along and the amount of weight I have gained already is crazy. I don't even know WHERE it's going, or how it's building up so fast. Maybe I just have a 20 pound baby in there? ok, i hope not. I know one thing, once he's born I'm going to be looking into how to get rid of belly fat fast! The diet and running I did in January worked pretty good, hopefully I can find the motivation to start again. It might be a little harder for me to get started since I will have 3 kids, plus the 2 that I watch during the day. I've been pretty tired and stressed lately, I know running will take that stress away, it was a great stress reliever. Maybe I should work on the diet thing now, I know eating better gave me more energy.