HELP?? Whats wrong with my chihuahua?!?

well my chihuahua is 7, and he wont eat he drank some water though.... and hes to tired to get up. we took him out side to go to the bathroom (we do that daily) and usually he runs and is excited to go out, but today he just walked and when he walks it doesnt look normal...and when i look at him, his left eye is like twitching and looks like its going to close.the other one is ok... and when i got home ... (hes usually excited, wags his tail, and runs around..) but this time he just stood up, and his tail was tucked in.. and it still is... and he just lays in his kennel...hes not himself... my parents said not to take him to the vet and wait til his next checkup... (which is in a while...and they said if we take him it would be very expensive... so they said no... but im worried about him... i dont want him to die:'(... wats wrong with him?? what can i do besides the vet??