When sales move, the useful question is not "what are my numbers" but "what changed, and which of it caused this". These are the checks we run, written out in full.
Sales fell overnight with no suspension and no email. Here is the order to check things in, and why the cause is almost never the dramatic thing you fear.
Traffic held but conversion fell. Use the organic versus PPC comparison to tell a listing problem from a traffic-mix problem before you change anything.
Organic rank fell on your money keywords. How to confirm it is your ASIN, find when it started, and tell a ranking loss from an ad-delivery loss.