Potty training in 3 days?

S • I married the one!!💍👫🧒🏼🧒🏼👶🏻& 2👼🏼👼🏼

So I am potty training my son with just his underwear he had a few incidents today and he was aware as he would say oh oh etc how did you do it? I have him in a timer of going to the bathroom every 15 minutes and he always pees before 😭 how did you do it? Was the second day better?