Hello and welcome.

Unfortunately, our news for you is not good. Your coin is a rather odd "mule" replica of two different ancient Judaean coins, both of which could be classifiable as "Widow's Mites".
The top pic, with an anchor on it, is taken from the "typical" Widow's mite, the prutah of Alexander Jannaeus (c.80 BC).
Wildwinds shows a bunch of them.
The bottom pic is derived from the Roman Provincial prutah of emperor Tiberius, dating from about the time of the Prefecturate of Pontius Pilate, roughly 33 AD: a simpulum, or Roman pouring-ladle.
Wildwinds example.
I call it a "replica" because it's physically impossible for a genuine coin to have been struck using two different dies originally used on coins over a hundred years apart. Whoever made it seems to have gotten their fake coin dies mixed up. Perhaps they mis-took the wheat-sheaf that's supposed to be on the back of the Roman-era coin for an anchor.
I suppose the important question now is, what's a fake Widow's Mite doing buried on the beach, and does it create doubt as to the authenticity of your Spanish coins? If they were found sort-of all together, they may have been a bunch of fake coins that somebody buried as a "pirate treasure hunt" that were never found.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis