strange rattle under hood

ok so I got my oil changed today cause I didn't have time to do it myself. after I left the Toyota place and got home to shut my engine off I heart a faint raddle/knockish sound under the hood for about 5 seconds. also when it idle I can hear a sloshish sound while inside the cab. any idea what's going on?

 

Didn't have an oil light on did ya? Did ya pop the hood and have a peek around? Oil level look okay? Did they go around and check every damn little thing in there like they try and get you to pay for while getting your oil changed? Gotta be something simple that they messed with.
As for the sloshing noise at idle thats kinda funky....i wouldnt think the two new issues would bethe same thing, but....idk....check your coolant level for the sloshing noise, could be hearing it from the heater core...

The rattle/knock, is this happening after shutdown?

 

slosh sound in the cab could be air in the heater core, OR there could be water trapped inside the condenser box for the A/C if the drain hole got plugged up during the winter.