Ok do not listen to that last lady....it does not matter if you are 14 and 190. What matters is that you are 190, but you are also 5'10!! So, you are fine in that area, don't worry. As far as benching.... If you are even doing 140, that is awesome!! How long have you been lifting....because that will play into it as well, but at 14, you are not yet expected to be able to bench your body weight, which is usually the goal! Nice job that you are working out, instead of sitting on the couch like most kids these days!
Height in proportion to weight is what determines if you are overweight, not age.
If you are 14 years of age, and weigh 190 Pounds you are severely overweight. Since you are benching 100 lb for reducing your weight, you are targeting absolutely right weight. See the link below for a ideal weight-height chart.