Since you were accessing your server remotely via a docker container (OpenVPN-AS presumably), once you turned it off you've lost access to that server. So far as SSH is concerned, unless you also forwarded the applicable ports for SSH to the router (doubtful since you were using a VPN in the first place), then no way of regaining control remotely.
Going forward though, it might not be a bad idea to instead look at the Wireguard plugin instead of an OpenVPN container as (while you'd still be in the same boat if you disabled it), you would be able to stop the array, disable docker etc and still maintain access at all times.