Should i be mad right now?

i was planning on investing in four companies yahoo, AMAT, GE, and AIG. now this was about 3 months ago yahoo, AMAT, and GE were all around 8-9 dollars a share now there between 16-17 dollars a share. AIG was bellow 40 cents and now its over a 1.60. the only reason why i didnt invest was because i didnt have the time nor enough money at the time to invest and now that i do its pretty high. can someone tell me if they think these will continue to rise or if they will turn around and plumet?