From the title, another heretic, gone already.
As someone said, to doubt Paul is to pull apart all of Christianity. I have read the New Testament in Greek. Paul's writings are hard, because he is so well educated, and uses a lot of hapax legomena, (a word used only ONCE in the whole New Testament) and lots of fancy words that writers like John and Peter do not use. That is one confirmation that Paul was indeed who he said he was - and that he was educated in Greek, and did not merely use the linga franca (common language) of the fishermen and carpenters. But it does not mean he was any better than the other apostles, just chosen for a very different reason - and part of that reason was not just to go to the Gentiles, but to leave us with the best theology the New Testament offers.
We have lots of study aids, and scholars who study the writings of Paul at a level most of us will never come near. They understand those hard words, in context, and they do not come up with any kind of conflict. I use numerous tools for studying the Greek, and NEVER have I seen anyone even hint that Paul might be a "false" apostle. Pure garbage!
For future reference, an easy but scholarly book on Paul is:
Introducing Paul: The Man, His Mission and His Message, by Michael F. Bird, IVP Press, 2008.
It might help someone with obviously false doctrine understand the New Testament and Paul a bit better.