That is completely normal so early in your recovery. You're not yet 3 months into a year-long recovery and your body is still recovering from the trauma of surgery and adapting to the new gait you have since your surgery.I have been struggling with muscle/joint pain recently which I never had before the surgery.
Even with metal on metal implants the incidence of metallosis was less than 10%, which means that more than 90% of people had no problem at all.I have read that even MOP (metal on polyethylene) can cause metal ions in the bloodstream which in turn can lead to health problems. Especially with cobalt/chrome heads
The incidence with metal on plastic is much lower than 10%, so it is extremely rare.
Instead of worrying yourself about something that is unlikely to happen, try to think more about being able to do again all the things that your bad hip has prevented you from doing.