Could you check the mint mark? If it's an S, your coin should be a proof issue. Normally proofs are hand-inspected at the mint so it's unlikely that an obvious error would be released. Plus, as a proof it should be in its original plastic mint holder. If the coin is not a proof but does have those two errors it would be hard to put a price on it without examination. You'd need to take it to a dealer who has expertise in error coins to have it evaluated in person. The bubble could be exactly that - sometimes a small amount of gas will be trapped in between the metal layers in the clad "sandwich" when they're bonded. The gas can result from contamination or other crud that wasn't removed completely before bonding. The gas can cause a bubble to appear when the coin is struck, or afterwards if exposed to significant temperature changes.