a big change for me

hi

i have been maintaining my weight relatively well since August 2011. However, I am underweight.

I haven't had periods in a year and therefore I need to gain weight, even though I like my body image.

Please could anybody give me some advice on macros/healthy ways to gain weight?

I am reasonably active with tennis, body pump, walking and starting netball again soon. i love food, i write about it, cook and have a passion for it but i am really struggling to come to terms that i need to have my period because i really love the way i look now - in my opinion it isn't overly skinny (you can't see all my bones for example)

anyway, i'm 17 and am planning to gain weight at 1/2 lb a week so MFP has put me at 1760 ( I was maintaining at 1560 + some exercsie cals)

thanks for any tips/help/support