Radiator not working

Hi all

I've a downstairs back room (2 bed terrace) radiator which is either first or last in line, i'm not sure. My spider sense tells me it's last.

I've tried balancing but without knowing the direction of flow i'm stuffed, no?

Can't 100% follow flow as two rads very close (bathroom upstairs and rear bedroom), and pipes under flooring.

Bled the sytem, only cold water.

Valve's work (they allow water to come out when bleeding).

Worked fine til 3 days ago, triggered i think by turning off and on both valves on all radiators upstairs.

Any help please??? :

If all the other rads work ok try turning them all off except the one that is not working and make sure the valves on the one in question are turned on.

has it got a themostatic rad valve?
when did it stop working?

It's working, i'm sooo happy.

Think i'd unbalanced it, thanks for your help.