Are you referring to Galatations chapter 2? That happened after the Council of Jerusalem. During the Council of Jerusalem, Peter had expressed his view in salvation by grace through faith alone, then afterwards began to withdraw and showed signs of changing his practice of eating with the Gentiles, etc. However Paul rebuked him for it, and evidently, Peter repented.
So I'm not sure, what your point is.
Evidently?...I really don't feel like making out a timeline, if you care you would read the two stories of Paul's ministry and contrast. How many times did Paul go to Jerusalem and meet with the apostles in Acts? How many in Galatians? How was their doctrine agreed upon? Did they all agree on the doctrine before they went out and ministered or were they teaching different doctrines?(who's doctrine wins out and why?)
Step out of 2013, read the text in context (like a historian) and it's a completely different experience than reading it as a believer in 2013 trying to find some kind of spiritual message.