Probably OK. I drove a 300D with no fluid showing on the dipstick. A mechanic in a hurry had replaced the engine and trans and forgot to add fluid to fill the torque converter, it shifted ok but felt kinda of sluggish, so after driving some 30 miles I checked the dip stick and found nothing showing. Still worked OK after it was topped up.
Smell your fluid, if it's burned smelling, and browninsh color its toasted and bands need replacement. if red and oily smelling, it isprobably fine...

__________________
'95 E320 Wagon my favorite road car. '99 E300D wolf in sheeps body, '87 300D Sportline suspension, '79 300TD w/ 617.952 engine at 367,750 and counting!