Yes, since both your incoming and outgoing connections are over the tor network, your IP is hidden.

Tor sends encrypted data from your machine to a first tor node, which can see your IP but not the data, then to a second which decrypts, then a third which knows the data but not your IP, and then that node is the broadcaster which foreign machines will see. In this way no one individual node knows all information.

Bitnodes can see your node because the IP is being forwarded, this will allow an external probe to detect your node. If you want it to not find it, try putting

listen=0

In your .conf file. I believe that should stop it.