Hi. I'm currently about 5'5 1/2, weighing about 122 pounds. I'm 14 years old as well. I aim for mass, so I do less reps with more weight. However, I can only bench about 80 or so pounds 3 times before i'm blown out. I've always been off and on with weight lifting, but now i'm wanting to get serious. I started more eating habits to go with my routine as well.