Is my cold wallet still cold?
That wouldn't be a cold wallet. A cold wallet is one where the private keys aren't stored on an Internet-connected device, even in encrypted form.
If you just want to check your balance, you should be able to export your addresses, and import them as a watch-only wallet, then keep the private key file (even encrypted) off of your computer. Also, 10+ BTC is far past the point at which I would just consider purchasing a hardware wallet.