Dulcolax are the best but you should also try Dulcoease first. Dulcoease is a stool softener and this is quite often more the problem that not being able to go at all. It's also much kinder. If that doesn't move things after a couple of days, then try the laxative. Don't forget to keep up the water.
Also, don't get obsessive and be patient and gentle with yourself or you could start a pendulum where you are going from one extreme to the other!!