I had the brakes replaced about a month ago, but now the front driver's side brakes are making a metal-on-metal rubbing sound. The last mechanic did not replace the caliper, which I think is the main problem.
Hello, brakes being one the most important systems on the car, this should be handled sooner rather than later and the vehicle should not be driven. I am unclear as to why you believe the caliper should have been replaced. The reason to replace a caliper is if it is leaking, broken, sticks, or is damaged. Calibers should be replaced in pairs, both fronts, or both rears. If the brakes were done about a month ago, you can take it back to whoever performed the brake job or you can call another mechanic to perform an independent inspection and repair.