I think you are OK.
It is possible #1 plug fouled and with a plug not firing, that cylinder will pass a lot of oil.
As stated before, check the points. When the points start to close up, you can loose ignition output and you may pick up a miss. Once a plug does not fire, it can foul and not fire until it is cleaned.
Also as stated by others, I would drive it and you may find everything is just fine.
My opinion,
Chris W.