Am I bulimic or overreacting?

Just before christmas I was really down on everything, and so I started to eat very little,anything I did eat I wud throw up later on. I didnt think I was doing anything wrong cause I was just not upta eating and I felt like I had to throw up. I didnt realise until my sister and mum confronted me and said they were worried. my dad kept telling me am going to end up in hospital and said if I didnt start eating then he’d take me to see the doctor the weekend coming up. I was so scared I didnt no what to do. Suddenly I realised that I could just eat and make them happy and throw up. then no 1 would have to know anything. This worked for ages but then I put on a lot of weight cause I didnt throw up everything.

Now, I throw up after Tea in the shower. I no that is apsoluty discusting but I have to. My sister kept catching me when I did it in the loo. She warned me not to do anything stupid. ( She had an eating disorder when she was younger) But I cant stop. So now when im in the shower I play my music with the shower going and no1 hears. 
But now I've got doubts. Im really really scared because  I dont want to do anything stupid and I dont want to end up how she did. but I really feel like I need to lose weight and I cant stop myself. 

I dont no if I am bulumic though or if im over reacting. I dont have breakfast. I have toast or something for dinner . Then Tea and then throw up . Am I or am I just being over the top ? Sorry if this seems stupid but I cant tell anyone cause I will just look like I want attention. But at the minute thats what I really dont want . Please tell me what to do xx