Is that my fault??

Went for dinner from library just now together with dear, Min Fei and Chee Han.. On the way, something's wrong with the car.... Then suddenly dear was looking at something and I noticed that the car in front was slowing down... The distance between that car and ours was already quite near and dear was slowing down at all since he was looking somewhere else... So I sort of "warned" him by making "ei ei" noise.... I was worried, of course, because we might just bang that car in front.. So dear was shocked by the "noise" I made and break a bit.... I admit I was a bit overreacted.. But who wouldn't do that at that situation?? He was not happy and replied me in a way that to me it's harsh... Will it be my fault as well if I saw that and didn't say anything about that, and then he banged that car?? Then I have to blame myself and being blamed for not saying or doing anything to prevent that...Yea, truly I felt innocent!!! The car was SERIOULY slowing down!! He was NOT looking at the road that time but somewhere else.. And the distance was already QUITE NEAR.... Well, it's still my fault... He is still unhappy and not talking to me since then... Okay, my reaction was TOO BIG!!!! Well, I'll just have to learn to keep quiet and stay cool~~~~~ What else can I say?!!?!!?!