Congratulations on your new Pacman Frog!
As mentioned before, often Pacman Frogs need time to adjust to their new home. It often takes several days for them to feel confortable with their new surroundings. Cody was actually eating the night I brough him home from a loud, busy Expo after an hour long drive to my house, but all Pacman Frogs are different LOL.
Superworms and Mealworms can be used as food sparingly, but I would only feed them that as adults, as said earlier. Nightcrawlers make a much better staple (don't forget to dust them!). If you get Nightcrawlers, you need to know that they are parasite and chemical free, or you risk losing your Pacman Frog. I am not sure if they have Walmarts in Canada, but I know Walmart has a strict policy to have the no chemical, no parasite at all. Many members have said they are safe. If you have a Walmart, it is the DMV brand. You can get baby Nightcrawlers averaging around 3-4". They are perfect in diameter for baby Pacman Frogs, the adults are stout and muscular.
Keep us up-to-date, and please don't hesitate to ask questions! If you haven't already, I strongly suggest you read the forum's Pacman Frog Care Article (located here: Frog Forum - Pacman and Horned Frogs - Ceratophrys - Care and Breeding ) if you haven't already. Even if you have already read other care articles, I think this one is the most accurate for the proper care of the species.