In the past I have often used the "is it me" method to make some very quick decisions. However it has often served me poorly. Possibly due to a poor definition of "me", but more likely I didn't really know enough about the things I was deciding. For example I didn't play sports for years because I didn't think it was me, too fast paced, too competitive etc. For various reason's I have gotten quite into fitness and outdoors activities such as cycling and tramping. I really feel that I was missing out all that time, the sports have really helped build my confidence and energy levels.
To quote Dave Matthews "If you hold on tight to what you think is your thing you may find your missing all the rest".