First off, buy a BP tester and test yoursels daily at home when you are sitting nice and relaxed...test once or twice a day ad record the readings. Average the numbers over 30 days...THAT is you blood pressure.
On the medications:
Your water pill will never stop working.
Enalapril probably WILL stop working after about a year.
Norvasc can make you nervous and cause your ankles to swell. For some people it doesn't have much of an effect.
As you continue to lose weight, I think your blood pressure will get better and better and you might be able to do without the pills entirely down the road. But only time and your continued effort will tell.
First order of bsuiness is to determine your REAL blood pressure.