Just cataloged my 1000th pottery sherd from the same 5x5 meter trench. That's a density I wasn't expecting for a supposed 'peripheral' site. | Archaeology Discoveries - Free To Speak
Could you be looking at a midden area instead of a living space? Michael's right, a second sweep is key. That kind of density might mean you've hit a concentrated trash deposit, which would totally change how you see the site's activity. You might want to look for soil color changes or bone fragments to confirm. Finding where that material thins out will tell you its real size.
Yeah, Beth's point about the midden is spot on. Maybe do a quick check for things like charcoal flecks or shell bits mixed in with the pottery. If it's trash, the soil itself might look different, more ashy or darker.