Dark bleeding

Wiped 12/31 and saw dark blood. Thought it was my period coming. Since then I've spotted occasionally alternating between brown-back-dark red.

Not sure what to do. Last period was 12/10-12/14

Implantation bleeding? Miscarriage? Idk what to think. When is okay to take a test? Any insight pls 👍 posted pic was from afternoon of 01/03. Most that has come yet