Ok so I have a problem with myself!?!

Ok so I have a problem with myself!?

I use to be underweight at 48 kg, and because ive recently upped my daily fluid intake (from near zero to sufficient) Ive increased by a kg. I have a weird compulsive thing where I check my weight every so often and its not a good thing because I want to become successful in sport (especially tennis) and I wouldnt mind getting some more muscle except not by bulking up (increasing eating intake) just by doing more weights however I do want to be more stronger and fitter just Im so damn worrried about gaining weight when I know I'll be healthy still, Im 170cm at 15 years of age and 49kg is the perfect weight for a teenager of that height and, however I want to stop caring about my damn weight and more about my sport skills, its brings me down so badly at times because I tend to have an almost anorexic outlook on eating which is pretty bad, also because Im worried about my looks (another anorexic perspective in life). How can I stop this madness and just be happy!?

well think of it this way! you need your food for battery so you can do good with your sports! but you also need food to stay skinny because if you dont eat you body will store you food so just think of food as a good thing that your body needs and what ever you do dont skip meals make sure your eating atleast 3 times a day i heard that 6 mini meals is the best way to go though! but make sure your eating! you definatly dont need to worry about your food making you fat because you already have a fast metabolism! and start lifting and stuff for your sport it wont make you fatter it will work to your benefit muscle burns fat and calories faster than bones! the scale #s may go up a bit BUT DONT BE SCARED! that is just showing that your good eating and excersising is working to your benefit! and the kg you are adding on is all muscle so you can do better in tennis i bet youll have 0 body fat so aslong as you are eating right and excersising YOUR PERFECT! i hope everything works well and good luck with tennis! just dont worry too much about the whole weight thing the more you worry the harder it will be so just go with the flow eat healthy and give yourself a yummy treat at the end of every week! <3