Please can you help - I think I want something negative when in fact I do not ?!

This has been an on going problem for me for quite a while now, basically I think I want something negative when in fact I don't think I do at all. I will say to myself in my head for example "you want to die" my mind says similar things to this then I seem to believe it doesn't matter anything negative it says I just seem to believe it.

I then will ask myself the question for example "do you want this to happen" and I can not think of an answer I just seem to think that I do want that to happen. Why would I think I would want something like that to happen when in fact I don't at all. Why does it seem true to me when deep down I know really that this is not right. Before I said this kind of stuff to myself I never once felt an urge for that to happen at all. So why when I say to myself "u want to die" I believe it? When really I feel that its not true deep down but why does it just seem true??

Please can you help me :)