Inner strength

It is amazing how a single small thing can ruin my whole evening and the day after.
I just had a meeting...and it didn't happen...So what?
Things like this shouldn't influence me at all. Yet sometimes I find it hard to keep my cool.
I am trying to find the core thing that is going to keep me whole even in such moments. But I am over emotional, sensing the world not only with my 5 senses, but also with my soul i guess. And when something happens it is touching me very deeply.
I was talking to Armando, he was trying to give me a reasonable explanation of how feelings should be slaves to the rational-self. I dunno if I will be able to master this through my life - I guess I should do it, as otherwise it will be quite a painful experience.
I am thinking that maybe I should start practicing some religion or philosophy...Budhism or something...Or maybe I should just reflect more, let the rational self tame the irrational "me".
Progress is very slow...