1999 Toyota Corolla Acceleration Sounds louder than normal

Just recently I was driving and then heard a little bang noise. All of a sudden next time I hit the acclereation it sounded louder than normal, like a rough sound (loud buzzing) I haven't really maintained the car, but its been running really good because I only drive the car 2 miles a day. I just want to know what it could be from the louder acceleration, also sometimes when I am accelerating when I park I hear a little rattling noise coming from underneath the car. I'm thinking a loose hose in the exhaust or something like that. If anyone had a similar noise or knows what it could be please let me know.