First of all, I believe you are inexperienced and you used a spell written by someone inexperienced. And this is a case of the blind leading the blind. That's what this indicates.
Wax is not a good glue. I don't know why anyone would think it would be. That's why it happened. Wax is not sticky. It hardens and then it becomes slick and smooth.
Secondly, a red candle is a lust spell, not a love spell. Red is for lustful passion. So you are trying to provoke carnal desire, not love. If you wanted to truly create a loving relationship with someone, you would have used pink which is equally acceptable for friendships--and everyone knows love needs a solid foundation of friendship for it to last. Red is used only if the relationship already has a solid foundation or if the person only cares about...well, the bedroom. So no, you should not do it again because you don't know what you're doing.