Batter hit by pitch??

[Stair-Climber]

Working girls ASA FP alone. R1 on 2B and running for 3B on the release. Pitch far inside and low. Batter jumps up and I believe (very sure) that I hear the ball hit the batter's shoe (really couldn't see it). I call dead ball, instructed batter to 1B and directed R1 back to 2B. Batter steps back up to plate to bat. I told the the batter tha she needed to go to 1B, but batter ignores me and is ready to bat again. I then asked batter, "Did the ball hit you?" Batter said that ball did not hit her and was determined on batting. At that point, I thought that maybe the pitched ball didn't hit her (I didn't see the actual contact). I allowed batter to bat, but made R1 go back to 2B because I had declared dead ball on what I thought was a hit batter. I know that most of you will tell me that I should have stayed with batter hit by pitch and ordered batter to 1B. Suggestions on how to handle this.

After inning was over, both coaches also thought that the ball his batter's foot, but, like me, wasn't 100 percent sure.