Re: how quickly do you gain or lose weight?
well you didn’t specify that before 
according to the webbernet, your ideal weight is 112 - 143, so you’re not too far off target. however, whats your BMI? a lot of research is now saying its not so much your weight as your BMI that dictates whether you’re healthy or not because it measures the amount of body fat that you have.
measure your BMI and see what it says
http://nhlbisupport.com/bmi/