New here. Struggling

This is my first time on this. A bit of background about myself: I have had an eating disorder for about 2 years now, and I don't really know exactly how to explain it but it tends to consist of me greatly restricting calories, and throwing up any extras or even sometimes just making myself purge what I'd usually eat (mainly salads). I know it isn't normal but when I stick to my restricted diet I am so happy and comfortable, although I do not like purging as I don't feel it works. I'd rather just not eat the crap in the first place. 

Recently I stopped weighing myself and put on about 5lbs. I am mortified. I don't want to go out anywhere incase people can see it and judge me and I struggle to even convince myself to go into sixthform (I am year 13, going to uni next year).

I am having a massive confidence crisis and now need to begin to shift this weight, but I'm so scared, I need it to happen now now now!! I can't stay like this, I am far too unhappy. 

I just need to get things off my chest. :/ thank you