Help cat is sick,vet doesn't open till 9?

I posted last night but got no helpful answers.We just moved and now my older cat is sick.Just a weelk ago my oldest dog died.She had gotten in the basement and eaten a whole tray of rat poison.I didn't know until too late. Now my cat is sick,and my husband thinks it is something on the property -he wants to move,I can't handle the stress.The cat didn't get into the poison-I threw it all away after the dog incident.I have three other animals and none of them are sick,they have been outside and inside and show none of the same symptoms of the cat.She is sleepy a lot,not eating hardly anything and having a bit of loose stools,or not going at all.She is old,and used to have seizures but hasn't had one in a long time(at least not in my presence) can someone please reassure me that our new home isn't killing my cat