Have a table that isn't compressed, put in a CHAR(20), insert a bunch of rows of 'aaaaaaaaaaaaaaaaaaaa'. Checkpoint the write.
Open up a file (.mdf or backup file) in a hex editor like HxD
If you see 'aaaaaaaaaaaaaaaaaaaa' in it, it's not encrypted. If you see other readable data (names, addresses, whatever other data you have) in it, it's not encrypted.
If you see random garbage (statistical character analysis shows roughly even numbers of every character), then it's at least compressed, and may or may not be encrypted, as both encryption and compression ideally result in data that is indistinguishable from random noise.