Brake question?

[GT Fanatic]

05 Infiniti G35 Sedan

I don't know if any of this is tied together some how. I just did the brakes on my wife's car cuz it sounded like the pads were gone. And at high speeds the car shakes when braking fast or slow. I did them last August as well cause of the same reason. So 5 days later the are sounding like the pads are gone again. WTH can cause the car to do this so quickly? I put ceramic pads on with decent rotors. Upgrade from the August job.

Also seemed like when i let off the gas car seemed shaky on the highway. Weird as hell. Thanks in advance for any and all help.

[redrocket5.0]

Warped rotors, possibly a caliper slide is sticking causing pads to wear out faster.

[GT Fanatic]

Sorry forgot to mention the pads I took off last Thursday had a lot of life left in them.

[GT Fanatic]

Can the ABS cause this to grab funny and sound like it's metal on metal?

[JimD]

Rotors are warped, new ones are not that expensive.

[GT Fanatic]

I just put new ones on, and the last ones started doing the same thing a little after install. I think it's something besides warped rotors. Is that possible?