Madrid forward Bale was booked for a high 68th-minute tackle on O'Shea during Friday's 0-0 draw in World Cup qualification.
The match also saw Everton's Seamus Coleman suffer a broken leg in a separate incident involving Neil Taylor, which led to a sending off for Wales full-back.
And Coleman's Ireland team-mate O'Shea felt he was fortunate to avoid more serious injury after needing several stitches to his shin.
"There is no problem getting a hard tackle but when people are very late, and stuff like that, it is a different story," O'Shea told reporters after the match.
"When I saw it back, yes, I was a little bit annoyed. It was one of 'them'.
"I have had plenty of stitches put in there. I was lucky considering what has happened to Seamus. On another night there could have been two red cards.
"In a derby game, you are going to expect some tasty tackles - but, as I said, within reason.
"I can't remember how many stitches it was. The doctor had to stick some in deep and a few dissolvable ones on top. Hopefully it will heal quickly.
"Thankfully I am walking away from it, so no problem."