Your question is full of errors and misconceptions. Paul died as a maryr at Rome, he may well have met Christ in his lifetime (there is much speculation on this subject), and Paul strongly believed himself to be preaching the Gospel of Jesus Christ - moreover, the early Church clearly agreed with him.
But what annoys me most is the attempt by some to paint Paul as a sexually-repressed reactionary, while Jesus was some spaced-out hippie. No. Actually read Jesus' words. Many of them are harsh and even violent. He rejects his own family, including his mother. He refers to Gentiles as dogs. He tells his disciples to arm themselves with swords. Much of Jesus' reported speech is bitter and harsh, and full of an urgent sense that the things of the world are passing away.
Paul, by contrast, often comes across as a rather gentle mystic. It is not Jesus but Paul who extols the virtue of love in a highly poetic passage in 1 Corinthians: "If I speak with the tongues of men and of angels, but do not have love, I have become a noisy gong or a clanging cymbal" (1 Cor 13). This is not Paul the legalistic extoller of righteousness. This is Paul the visionary, whose message was one of mystical union with the Christ he worshipped.
Paul was the first and greatest Christian theologian - he assembled the confused accounts of Jesus' life and ministry into a coherent theological system. But it is probably not the case - as many assume - that he personally came up with everything written in the Pauline Epistles. On the contrary, Paul seems to be reflecting beliefs that were already widespread within the Christian community within a decade or two of the crucifixion.

