The only way to test if the problem is the card or the camera is to try another memory card in the camera. You can also try to read the card with your computer using a card reader.
If the computer cannot see/read the card, try formating the card in the reader and then see if the camera will recognize it. If it does, then format the card in the camera.
If the computer cannot even format the card, then it (hopefully) is just the card.