It's terrible what we all go through, always worrying about dying and getting sick. Trust me though, it does and will get better. There are times where I wake up at the very same time each night and my heart is pounding and racing, then to make things worse I start to worry and of course it makes things worse. I end up having to spend 20-30 minutes trying to get back to sleep.
I don't know about any of you, but I find that if I have had decent full day(day where i've done alot physically and mentally) I tend to sleep very well. You can try reading a book before you go to bed, this takes your mind off things a little.
Xanax does work wonders if you have any, if you take one (.5 mg for me) right before you go to bed, it makes a difference.
If you aren't on any kind of medication, I think you better seek help. If you can't afford to do so, don't worry there tons of local programs to help you. (here in the u.S.A.) not sure about other countries ...