Red and black oblong beetle?
 

Picture attached. I believe this came in with a plant. Or maybe came from outside? I've never seen one before. I spotted it crawling around on the leaves today, but it doesn't look like it's doing a ton of damage. Should I be worried? My initial googling made me think it was a dendrobium beetle, Stethopachys formosa, but I don't have any orchids from Australia and the head color is wrong.

Send the photo to the biology or entomology department at any one of your numerous Pennsylvania universities.

Maybe a type of clerid beetle or Clytra laeviuscula?

An amazing resource for any kind of wildlife ID is iNaturalist and their phone app called Seek.

The Seek app uses computer image recognition to generate ID. It's not perfect but still works amazingly well for local wildlife. Not as good for exotic houseplants since it uses your location to help guess. The image recognition algorithm is trained on all the photos uploaded to iNaturalist.

For iNaturalist you need to create an account; you can use the same image recognition software as Seek to generate a potential ID before you post, but your pics are then verified by the community.

I ran your pic through Seek and it thinks the genus is Anthocomus, possibly Anthocomus equestris

I should have thought of this myself! I actually once worked in an entomology lab; the professor did occasionally field identification requests from the community!

This is an incredible resource that I was unaware of. Thank you!

For those who have Android phones, the Google Photos app has a handy "Lens" button that will give you suggestions as to what your picture might be. In this case it also suggested anthocomus equestris.