Caribbean - Laundry near OSJ Downtown pier

Hi...just a quick question...we will be on a 12 night cruise in a couple weeks stopping in SJ.....does anyone know if there is a laundromat nearby??? Our ship docks in OSJ near the Sheraton...i can walk a bit.....we are there from 3-10 PM

Thanks...(or would I be better off asking nicely at the SHeraton?? I am an SPG Plat member!)