That's exactly what mine did with a cal-mag deficiency.
I thought it was light burn although it wasn't close enough to be.
But when I asked i was told to try a cal-mag supplement and it worked like a charm.
I'm new too but I just wanted to say that mine did start out with 1 like that and got more within day.
Good luck, she's pretty otherwise and the one I had do it is now my most beautiful plant to date.