Flumby

My partner opened and did no bid. Our opponents bid 1 heart, I had a hand of 10 points with even distribution. I replied no bid. When the bid got back to my partner he bid 1 NT. Opposition bidded no bid. What should my response be???? I bidded 2NT! My partner was not happy and got very annoyed. I see him tmw and would like to know anyones advice. To me a no bid starter means he does not have 12 points. When he bids 1 nt he has a weak nt with even distribution the same as me. I had no 5 card suits so had nothing to offer in a single suit so I bid 2 NT! should I have left it at 1 NT?!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! HELP