VB.NET Memory Management

Question

I have a project that consists of about 30 forms. I go from form to form and everytime i create a form I set it to Nothing and when I close the form I say Me.Dispose(). I also have a database connection which I also say .Dispose() when finished. Unfortunately the memory keeps increasing everytime I open a new form even though the previous form closes. Also if I say something = Nothing then the garbage collector should take care of it, right? Thanx