Running the 40/20 sheathing with an incorrectly oriented strength axis as you have, the bending stiffness of your floor will be at most (56000#-in²/ft)/(250000#-in²/ft)100% = 22% of the correctly oriented stiffness. As the number of plies goes down from 5, this percentage goes down. The numbers come from page 52 of the AWC's Manual of Engineered Wood Construction. Your sheathing was unnecessarily thick, though, so maybe the reserve strength can salvage the installation.
For something small like a shed, the goof shouldn't impact structural stability. Technically your floor sheathing is also a floor diaphragm that could be transmitting some wind load depending on how this shed sits on the ground. With only 16 ft of width, I'm sure it's fine.
Floor strength and deflection for people walking around is a problem, however. Technically there isn't a spec for incorrectly oriented sheathing. The span ratings for sheathing are defined by performance tests prescribed under NIST PS 1-19. Among the tests, there's impact testing based on ASTM E661 for correctly oriented sheathing, but no impact testing for incorrectly oriented sheathing. Without impact performance data for your 40/20 sheathing, there's no way to verify its adequacy against impact requirements.
Apart from the impact performance, I can look in Table M9.2-1 of the AWC's Manual of Engineered Wood Construction to find the minimum bending strength and stiffness for correctly oriented */16 sheathing (385#-in/ft and 86,000#-in²/ft). I can look up the corresponding values for the non-strength axis of your 40/20 sheathing (270#-in/ft and 56,000#-in²/ft). Comparing values, I conclude that your bending demand is at (385/270)100% = 143% of capacity and that your deflections are at (86000/56000)100% = 154% of maximum. In your case, then, I can conclusively say that the incorrectly oriented 40/20 sheathing is out of spec.
Remember, even if the incorrectly installed sheathing satisfied bending strength and stiffness requirements, I would still conclude that your sheathing is out of spec because of the impact thing.