I'll be 38 weeks pregnant tomorrow. Yesterday I was vomiting and feeling sick. I have constant bh for the last 2 days, also at night when I need to use the toilet I leak clear fluid and then go. Is all this normal?

YOu need to call your Dr. or go to the LD to get checked out. Any number of things could be going on.

Some women will experience a "cleaning out" prior to labor or in very early labor. How often are you having the braxton hicks? If more than 4 or 5 in an hour, contact your midwife or doctor... get plenty to drink, get something to eat, go to the bathroom, change your position. These types of activities will usually cause braxton hicks contractions to subside. True labor contractions will continue. Also, being a bit dehydrated can cause your uterus to contract more so be sure you are taking in adequate fluids.
Does the clear fluid continue to leak or only when you use the toilet? Sometimes a small tear in the amniotic sac will result in a small leak of fluid. You may feel like you have to go to the toilet, you go, but you still have fluid leaking out every now and then. There can also be a fair amount of natural discharge towards the end of pregnancy as well, but this won't usually result in a constant leak.

When in doubt, give your care provider a call. They might have you go in to see if what you are feeling is amniotic fluid, put you on the monitor to see what is going on with contractions, and do a pelvic exam to see if there is any change to your cervix.