I don't know what exactly happened, but I can pretty much guarantee that you didn't do anything that hurt Lincoln, or that caused him any pain, or that can't be forgotten with a little bit of time and love. I think I can safely say that pretty much everyone in the entire world who has purchased a harness for their parrot has made the exact same mistake that you just did at least once, myself included. I think the general feeling for a lot of experienced parrot owners who have a close relationship with their birds goes something like this: (After reading the step-by-step process for getting the bird to put the harness on, and then the second process for getting the bird to accept wearing the harness, and then chucking the instructions and/or the Training-DVD that came with harness into the trash)..."Well that's a waste of time; this must be for people who either have their first bird, or who have a bird that isn't tame, or for people who aren't bonded closely to their bird and can't handle them. I don't need to waste an entire month on just loop over his head and then taking it off again, that's just stupid. I'm going to take Bowie out with me later this afternoon on the harness, there's nothing to this...".
...Or some form of the above thought process, lol. We've all made this mistake, we've all found out exactly why the Aviator Harness comes with a Training-DVD, lol, and we all now-know why there are so many people posting on the forums about how impossible it's been getting their birds to wear the harness. As long as you learn from the mistake and do it the right way next time, then it will be fine.
Lincoln loves you, and this isn't going to change that. They can be ultra-sensitive and sooooo stubborn at times, but as you said, he's already acting normally towards you, so there ya go...Just "Hit the Reset-Button" right now, pretend like that little event or episode never even happened, and start-over again from step #1.