i am a pro mayo maker, will help you for next batch :-)

only put yolk, not the white!!!

mix with your mixer and then add few drops of oil only, mix again, few drops, mix, slowly slowly you can put more

when it gets thick thick, then add vinegar and again some oil to get the consistency you want

if it goes wrong, you have to start with a fresh yolk and slowly add your mixture inside, not the other way around

good luck :-)