I am trying to gain weight?

Well i was told by some people that you should intake 3500 calories to gain one pound. I weighed 135 pounds and im trying to get to 155. I have been eating more and taking serious mass shakes from bodybuilding.com for about a month now and i am up to 146 right now. I eat about 4000-45000 calories a day and it seems to be working. I also work out alot to so that is probably helping to. Thats what i do and it is working so far.