HP Lovecraft fans, I'm a bit confused about the ending of "The Tomb".?

Ok I'm sorry if this is a stupid question but I just got done reading HP Lovecraft's "The Tomb" and I wasn't too sure if I understood it and want to know if I understood it correctly because I'm a bit confused about the end. I came to the conclusion that Jervas is a reincarnatted soul of a member of the Hyde family, and when he was having the hallucination of the party in the Hyde manor and he was witnessing its destruction as well as his own death in the past life and that's why the two men find that painting in the ruins that looks like him as well as while Jervas is in the asylum and Hiram tells him about the empty coffin in the tomb with "Jervas" engraved on it, Am I correct because I wasn't too sure?