i agree you need to get the cat to the vet asap. if you cant get her to feed the kittens then you need to bottle feed them. if the formula from the vet is too expensive then you can get some from your local pet store. make sure its the right kind. there is a milk re-placer and a milk supplement. make sure you get the milk re-placer the supplement is in addition to regular food. it comes in both liquid and powder. i prefer powder but the type you get is up to you. mix the formula as indicated on the back. when you get a bottle cut a x on the top of the nipple and make sure the formula flows when you gently squeeze the bottle. the formula should be warm not hot. test it on your wrist. it can be a little difficult for you to get them to eat at first but do not give up. at this age they will probably only eat about a bottle between all 5 of them. if they eat more then great. bit if they have not eaten from their mom yet you need to do this NOW or they will start to go down hill due to lack of nutrition.
you must get her to a Vet immediately, I don't know whats wrong but the shakes sound like she could be running a fever, if she is this sick she will be unable to nurse the kittens and they MUST eat and SOON, little ones that small cannot go many hours without nursing...this would be fatal for them, you would need to bottle feed them a formula from your Vet if the mother is too ill to feed them...please get her some help and quickly...yes you had best try to put her back in the room with the babies and see if she nurses them...but get her to a Vet right after please...
keep us updated...sending some prayers...♥