Port forwarding & OpenVPN

Question

I have a raspberry pi running Debian (raspbian) and I'm having issues that don't seem raspberry pi related.

I connect to this device via ssh most of the time on my local network, but decided I would like to control it externally, so I forwarded the port.

No luck

I have OpenVPN connected at all times on this device and IPtables blocking all non-essential incoming ports on the tunnel.

So, what seems to be happening is: When connected to VPN, port forwarding doesn't work, when not connected it works fine... (appears as filtered when not working)

I've got no idea what's going on, I tried allowing all on the iptables but this didn't seem to make a difference.

Any ideas?