Can I take over-the-counter pain relievers if I'm using lidocaine ointment 5%?

Yes. Other the counter pain relievers (i.e. Advil, tylenol, (acetaminophen) aleve, aspirin) are different classes of medications to local anesthetics (e.G lidocaine, benzocaine). So there will not be a reaction or overdose. I would however avoid any throat sprays that contain Benzocaine or cetacaine. Although the probability of a local anesthetic overdose is very small, why take the risk.