What are some otc pills that look like this?

I had a scrip for vics from a back injury last year...long story short I took a few the other night for pain and they have no effect. I don't remember what they look like, but I have a suspicion someone may have swapped them out with motrin or something.. I just want to know what I took, if that's the case. Anyone have any clues? Basically it looks just like this, only nothing on it... i think, I don't have them with me.