My Dx is Type 2 - but my situation was similar, and opposite -- despite my age at Dx (50), my PCP looked at my activity level, my diet, and the fact that I was NOT overweight and was unhappy with a Type 2 diagnosis. Prior to Dx, I felt very good - better than I have felt perhaps my whole life -- a feeling of well-being that ended (and has not returned) as soon as I started managing my BG... Still, my PCP did try T2D meds first with somewhat acceptable results, but VERY unacceptable side-effects - and the added effect that at no point during that time did I feel the least bit 'well' -- After a fairly short time of just a few months, he decided that there HAD to be more to my case and referred me to a specialist.
The endo tested me for LADA, but, despite a somewhat low c-peptide test, the negative result on the antibody test left the Dx the same. He did get me on a CGM, which has helped. Last year, I changed endos, and the new one also got me on a pump... Still Dx'd as Type 2 and destined to fight with insurance over D-tech, but at least, for now, I have tools that are helping me.
Now... I just have to get back to really feeling well again!