Does Paul contradict Jesus?

In 2 Peter, Peter writes about how Paul's letters are hard to understand and can be confusing. If it was confusing to people who were actually around him in that time period, do you think it might also be hard for us to understand some of the things he was saying? When reading anything other than what Jesus said (especially Paul's letters) it is most important to base everything off of what Jesus said. For example Paul says "being kind to your enemies is like pouring hot coals on their heads". Do this mean it's good to pour hot coals on our enemies head? Of course not, because we know that one it is a metaphor, but more importantly we know Jesus taught people to love their enemies. Take a look at some really easy to mistake and confusing writings of Paul and how to line them up with what Jesus taught.