Hey there chick,
Sorry that you're having such a hard time. Today, there are just 3 things that I would recommend you do.
Firstly, I would like you to go to the nearest GP practice and impress upon the receptionist the urgency of you both registering and seeing a doctor right away. If your university has it's own recommended surgery, try that one first as they will be more aware and used to some of the issues that you are battling. Tell the doctor that you have been having suicidal thoughts and that you're scared of losing control. S/he will probably then ask you a series of questions to ascertain your current state of mind and situation. Don't be scared to answer them truthfully, don't feel like you have to hide your emotions. If you want to cry, then do. The doctor will probably then suggest a course of anti-depressants. This is a good thing. You are not failing yourself by having the aid of some medicine for a while. You are being strong by recognising that this is a positive way forward. Feel good about yourself for taking the first step of a journey to get back on track.
Secondly, do some research on the support mechanisms at your uni. Look at the uni webpages and also your student union pages. Do you feel able to tell us which uni you are at? For example, if you were at Birmingham, I'd be able to give you much more direct advice about what you can access and what to expect. If you doctor doesn't mention it, ask him/her about getting access to counselling.
Thirdly, go back to your flat, have a bath, a bit of a sleep and chill out and then knock on the door of your next door neighbour, or someone else that you may have seen as being nice, and say "I was thinking of getting a DVD out tonight - fancy watching anything?" If you don't feel up to this, don't worry, but it might help to forge a bit of a friendship and to make you feel less lonely. With a DVD there isn't the forced awkward conversations, and you can just lose yourself in the movie.
If you want to PM me, please do and I'll try and help.
You can do this. Remember that you are special to lots of people, and that everyone's lives are interlinked. Mine has already been touched by yours.
Best wishes for a better day today,
Cxx