2006 Automatic Transmission question

Hi. For the first few years I had my truck, I took care of all the maintenance (oil changes, brakes, etc.). But then work got super busy, so my wife would take the truck for maintenance. Life has now calmed back down, and I did my first oil change in a long time. I wasn't really paying attention, though, and I removed the ATF drain plug instead of the oil drain plug. I did realize it right away, given the color of the fluid, and I put the plug right back in. I'm not sure how much drained out, but it wasn't a lot.

And after finishing my oil change, I went to try and check the ATF level...but I've learned on the 2005-2006 models, you cannot easily do this. I have found a pdf of the instructions on how to check the fluid level (attached here), but 'checking' the level is actually just ensuring there's enough in the drain pan to trickle out of the overflow tube, which I'm sure there's not now.

My question is this: The instructions indicate the transmission requires Toyota Genuine ATF WS transmission fluid, which I don't have. Will it hurt the transmission to run a little low as I go to get more fluid? Sort of limited on vehicles. And, once I get

Totally my brain-fart, and super frustrated at myself, and I don't want to make matters worse. Sure appreciate any thoughts or advice.

 

Can you possibly make an estimate on what "wasn't a lot" means....quart, cup, 1/2 cup ?

 

If it was only a little you should be ok to drive, But you should just Uber it to vatozone. You will also need a piece of 1/2”I’d hose or with a thin wall, you can stick it in the full port at the back of the tranny and run it up near the firewall and put a funnel there.

 

https://tundraheadquarters.com/wp-content/uploads/2010/06/tundra-transmission-fluid-flush-tsb.pdf

 

Good morning. Thanks for the input. I would estimate a cup came out. I caught it pretty quick. I'll see what i can do to get it topped off, but will also probably have the tranny serviced. It's at 162k, so probably good to do anyway...although that fluid looked pretty clean and red. Expensive lesson learned. Thanks folks!