Does it look any different to normal dmt? Just wondering if theres anyway to actually tell.

Yeah, DMT N-Oxide is a yellow oil. Some yellowish DMT may have DMT N-Oxide in it, or it could be any number of impurities from the extraction.

^^^^^^^^^yup

if you use a fan to evap your solvent, you'll probably wind up with either a yellow gunk on the bottom of your crystals, or a slight yellow color infused in your crystals. I like to make nice white crystals and then re-x with a fan to add some n-oxide for a smoother ride and a yellow-tinged spice that I can be reasonably sure is yellow due to n-oxide and not random mimosa alks.