I bought a Patek Philippe Watch for $400.00. It is Grand complication 5002J. Is it real?

If it's real, how much should the price be? Also, I just check the watch after I got it, and I can't tell if it's real or not since they told me it's real. Do you have any idea about how much it should have cost?|||400? You were ripped off. I guarantee its fake.