It was running ok, now it’s terrible, I need help!!!

or water in it. or just really rich.
Or dirty points/wrong condenser.
Since this was the last thing changed ....... I would put the old condenser back in it, and clean the points. . If you greased the pointcam with some thin grease that has flown off ....... well, get the right stuff, and clean, clean,clean.
Popping in the exhaust COULD also be caused by air entering the exhaust system somewhere within the first few feet from the head , AND one of the following; 1) either a rich mixture or 2) late ignition timing;