In my 2020 return I forgot to add my 1099-R for 401K rollover (Code G)and $140 in self-emp income. My return is still processing. Do I file an amended return now or wait?

My original return was filed on February 12th and refund status says it is still processing after 2 months. I forgot $140 because I never received any document for it (no 1099, nothing whatsoever). 1099-R, I just forgot although I knew I had to do it. It has code G and I didn't took a single penny for myself. A simple rollover from previous employer 401K to the current employer 401K