2003 Tacoma Transmission Question

Hello everyone. Im new to the forum and I have a question regarding my 2003 Toyota Tacoma Prerunner TRD. It has the 3.4 L V6 engine.

I did my oil change and decided to check my transmission fluid for color and level. Since Ownership I haven't checked it (Aprox 7 months) My driving is moderate and average about 12,000 miles a year. No slippage or hard shifts noticed. It shifts positively, noticeable, and seems solid. It has never appeared abnormal.

I checked it when it was warm and did the recommended sequence to check the tranny fluid level (running through the gears after driving it for about 10-15 min). I noticed it was below the cold line by about 1" or so. I put 3/4 of a quart into the transmission of the ATF toyota fluid. The current fluid color is off red, not burnt or black that should spike concern.

It now reads between the cold marks WHEN cold. HOWEVER, when I do the same test it never reaches the Hot marks. It goes down slightly, then once cooled, back to the cold marks. Is this normal? Any suggestions on what to do? I dont want to damage my transmission by putting to much in. Any insight would be great! Thank you!