My Sheltie Ate Something That Made Him Sick

Question
I have a 12 year old Sheltie Male.Yesterday he was his usual perky self but I noticed he had snatched an old rawhide from my rat terrier, Laura and was gulping it down. And the next day when I went to feed my dogs, I noticed he was slightly depressed and quite tired.I did not offer him any food because I knew he wouldn't eat it... he never does when he gets lke this.But later my mom gave him a saltine cracker and he did eat that.he followed me around and drank plenty of water today.It has been hot. He has vomited twice now and the vomit is a liquidy yellow {the same color as that rawhide he ate} i have not feed him anything except the cracker and that's only because he was willing to eat it.It is obvious he is really sick on his stomache.I checked his temperature but he did not feel hot.I managed to give him a teaspoon full of organic flax seed oil.I have done a lot of research on it and I think it's probably the best medicine for him.I think he will be alright as he was way sicker than this last year but if anyone has any good tips on how I can help him get better faster then please help.He won't eat right now but seems to enjoy icy water.His tongue has been lapping out and he has rested all day and was shivering about 15 minutes ago.I did wrap him up in a blanket I got off my bed but I don't know how long he'll stay in it.If there is anything I should do for my dog then please tell me!Thanks so much.I love my dog as much as a mother loves a child.I don't want anything bad to happen to my best friend, Cheeko.

Answer
Hi Haley!
When a dog doesn't want to eat, it's a sure sign something is wrong.  The rawhide he ate may have spoiled on his stomach.  At any rate if he coninues to shun food, I would take him in for a Vet check up.  The refusal to eat, the shivering, vomiting and lack of energy mean more than just a "spell" he is going through. If he isn't better by tomorrow, I highly advise you have him checked out.
I know you love him, I can tell that you do!

God Bless,
Becky