97k Damage? Can you mention what ships you dealt damage to?
Credit Earnings are altered depending on the Tier of ship you attack. Also, credits are calculated based on %health done, not raw damage, so 97k to a Battleship would be roughly one player's worth of "Health", whereas 20k damage to 5 Destroyers would be something akin to 4.5 players. In short, target selection can be a huge factor in Credit and XP earnings.
If you'd like to learn more about our Economy, there's a great video which details it.
Direct Video Link: https://www.youtube.com/watch?v=0_bXHAqLkKc