Invalid fair catch

[stegenref]

So I had my first invalid fair catch signal Friday night, but I think I might have screwed it up. I'm posting it here for discussion / advice...please no flaming / bashing.

R1 is in a position to field a punt. As the ball is in flight, I see his two hands come up in front of his chest and kind of swipe across his chest...almost like he was brushing some crumbs off the front of his jersey. I remember thinking, "Was that supposed to be a fair catch signal?" and thinking, "No way, that was way too subtle to be considered a signal." Of course I only had a milli-second to think that because then he caught the ball and a horde of defenders came running up on him. Well evidently he thought he gave a good signal, because he made no attempt at a return and just casually turned toward me and started walking toward me to hand me the ball. All the defenders stopped and were standing right in front of him. I never blew my whistle, because in my mind I was thinking, "That's a live ball, why is no one tackling him". Everyone turned and looked at me, and as soon as the defenders realized I hadn't blown the whistle, they turned back and started tackling the kid. I realized then that I'd better kill the play or that kid was going to get hurt, so I blew my whistle dead and gave R the ball at that spot.

R1 came up to me after the play and was like, "Why'd you let them hit me, I gave a fair catch signal!". I told him, "No you didn't, a fair catch signal is one arm extended above the head, waving back and forth".

Looking back on it, and after researching it, I think maybe that as soon as I realized that R1 had thought he'd given a fair catch signal, I should've blown it dead for his protection and thrown a flag on him for an invalid fair catch signal.