Sickness or lack there of is no indication of gender!
I'm sick every day right until they pop out, regardless of sex (I have a girl and a boy and a surprise on the way).
The chinese gender charts are not always accurate either..
As for the ring test, that can be fairly accurate, but of course, nothing is going to be 100% accurate...
With the ring test, make sure you hold the ring (or whatever object, it doesn't have to be a ring) over your palm and ask it to show you boy and then ask it to show you girl.
Then try it over your belly.
Other than that, you'll just have to wait for a) an ultrasound where it's all clearly visible or b) the birth!!