Can’t sleep, don’t want to wake up!

Has anyone increased their dosage of citalopram? If so, did the increase make you feel worse before you felt better? Cause I’ve been pretty much suicidal for the last 4 days, I can’t sleep now cause all I can think about is ending it. If I had helium here I’d be gone already, but I only have a knife so keep sitting pressing it into my skin to see if I can cut… I can’t, too scared of the pain, but I just really, really, REALLY don’t want to wake up tomorrow. I don’t know what to do with myself. I’d hook my car up but it’ll wake my housemates cause it’s noisy. I don’t want to do this any more. I don’t want to be this person any more. I’ve tried everything to change, self help, cbt, regular therapy, hypnosis. I think I’m fundamentally and irreparably broken. I don’t want to continue if this is it. I wish I had the strength to end it…