Turbo Tax will always say Ready to Mail. They don't know when or if you actually mailed it and the IRS doesn't tell or update Turbo Tax when they get your return.
4 weeks after mailing you can start checking IRS Where's my refund
https://www.irs.gov/refunds/
Did you get a tracking number from the post office? And mail federal and state in separate envelopes to different places?