Just remember, the earlier you start a child potty training, the longer it may take to train overall. I can take a while for the muscles and all to develop. So it may be a while that your son will have some successes and some not. One thing I found is to let them practice going at every diaper change, before bed, when they get up, etc. Track him to see signs of when they will wet or poop, then take them then. Don't worry about your son not going for the rest of the day if he poops once. He may change his pooping habits with potty training. One of my triplets did completely.
Once you feel he's ready, do panties or naked and go for it, cold turkey. Time him and have him sit every 10, 15, 20 minutes, etc. He's going to have accidents. He may even regress at times. But as he masters one time interval, go to the next. Keep a roll of paper towels and Lysol wipes/spray handy for wet floors, and have him help in the clean up process. He needs to be able to pull his panties up and down on his own as well. Trained means "on his own" so you need to work him towards that. Flush himself, pulling panties up and down, climbing up and down, etc. Wiping is hard so that you can do.
Pull Ups are great, if you use them for the right purpose. They are too close to diapers to use during regular training. I used them towards the end of training. When we would go out, I used them just in case there was an accident, but I still pottied my kids often when out. I used them in transition for night training. When they showed signs of being less wet we'd switch to those and do the pep talk every time they laid down. Once they stay consistently dry for a while then I took them away to panties.
Night training will take longer than day training. Don't connect the two. Generally, children don't have control as easily over their bodies while sleeping, so it takes longer to learn to stay dry during nap/night. Some takes only a week, some may take up to a year to night train. That's ok!
You're correct, don't push. But also, don't over think and over analyze. It is what it is, training, and it takes time. Stay firm and consistent when full training begins. Never punish, but talk firm to let him know what he should and shouldn't do, and have him help clean up. I'd dry the pee on the floor and have mine use a Lysol wipe to disinfect the spot, then throw it away. Then go hand wash and talk about it.
You may want to think giving gifts for every potty success. When he goes 10 times in a day, that'll get costly, and also he's going to expect those big things. I would stay with a sticker or one M&M, something small but worth something to them.
Good luck!
K. B
mother of 5 including triplets