Can I sue notary for notarizing my signature without witnessing it and not even meeting me.

Unclear from the post whether she forged your signature

Did you actually sign? The notary might be in trouble, but you still may be held to the agreement.

Sounds like you need a business litigation lawyer either way, as claims are being made against you.

Your question lacks sufficient clarity. If you entered into an agreement, then you are likely obligated to pay the agreed upon amount. If you contend you already paid the agreed upon amount and that the seller has some how altered the purchase price in the agreement and is seeking additional money from you, then there may be a question of fraud. Whether you have a claim directly against the notary is questionable, but you may be able to report them if you feel that have done something wrong. You should consult with an attorney in your area to discuss all of the issues and provide sufficient details. You should be ready at such a consultation to provide a copy of any written documents surrounding the agreement, any correspondence concerning payments or the request to pay more, and copies of any payments made.

Contracts are not required to be notarized. If you signed it, you are bound by it, unless there is some fact that would void the contract. You need to have a lawyer review the actual contract to see if you have a way to void it. But the notary issue is not going to do it