Hi - Well, I'm obviously not Lenin, but I definitely can relate to your problem.
I started on 5mg. of Norvasc last year but immediately started feeling anxious and had trouble sleeping (I take it at night). I read somewhere that some take only 1/2 dose and have had the nervous feeling disappear.
My doctor was skeptical but said that I could try cutting the pill in half. It has worked perfectly! I also take enalapril twice a day; but my systolic pressure started to have high readings; thus, the addition of Norvasc.
My doctor said that it doesn't matter if I don't cut the pill exactly in half because it stays in the system and eventually evens out.
I certainly would never want to take that combination pill of Norvasc and another drug (I think the other drug is a statin).
Good luck! I'm glad to know that you went back on the 1/2 dose! It lowered my systolic pressure right away, so I didn't need the higher dose!