I have a seven month old son who was born premature and was on aheart monitor he was just took of this week he is now 7 months but I am terrifed of him getting sids I can't even sleep so terrified of him dying what can I do:(

That is definitely going to drive you crazy unless you get your head together. Don't lay him on fluffy sheets that he can sink into when on his back, don't place him on his tummy with his head on the side. Make sure he has a firm mattress and nothing in his mouth like a bottle (I hope you don't put him to bed with a bottle, or pacifier - please don't take offence). Many caring mothers think this is what's needed. Get a baby monitor if he in a separate room. Have his crib in your room, have him napping where you are during the day. What can I say, love, its hard I know, my son was small when he was born 6 lbs. 3 oz. or so. He and survived and you should see him now at 25!!

You know what you do get over this, my daughter was 8 weeks prem weighing only 2lbs 9oz she came home 8 weeks later she actually has a heart condition and was and still is absolutely fine she is now 2 I kept her in our room till she was 6 months old till I could stand no more of the snuffling and grunting in her sleep and decided I needed the sleep.
I only used a normal baby monitor but you can buy then that detects there heart rate like what they use in the prem unit but its not attached to them.
BLISS the premature baby charity these guys are a uk based charity I'm not sure where you are hunn but there's bound to be similar in your country they are an amazing help and support just remember hunn you aren't alone and every mother there ever has been has felt afraid at some point.
Hugs xxxxx

Have the doctors informed you that there's an increased risk of SIDS? If not, I wouldn't spend too much time worrying. Most premature babies, given proper care in the early weeks of life, go on to be perfectly normal, healthy adults.