20 month old pulling at nappy is this a sign?

[Covidtrap]

Ive noticed over the past 2 days my son has started pulling at his pants. He seems to stopcwhat hes doing, try and adjust his pants then keeps pulling and when i check hes done a fresh wee. Is this a sign its time for me to start getting him familiar with the potty? First time single mum here so i dont really know what im looking for or meant to be doing but it does seem to me as though hes holding his urine in longer, doing bigger wees and now this pulling has started after he does a wee.

My dd started doing this when she was ready. I started by putting the potty in view of her so she could explore it abit and told her what it's for. I sat her on it a few times during the day and made a massive fuss when she did something in the potty. I also swapped her nappy for pants and yes I had a few accidents to clean up but she soon realised she didn't like the wet feel and it encouraged her to use the potty. I never told her off when she did have an accident. Does your ds know the words wee/poo? I know that sounds silly but it just made it easier when I was potty training to tell her thats where she goes. Just remember every baby is different and he will have set backs and that's OK but he'll get there. Good luck

Id advise reading the nhs website that has z full guide of signs and how to start.
You can see how long he holds a wee by putting tissue in his nappy it needs to be dry for at least an hour.
It maybe a sign or it could bd practising z new skill see what else he dose and maybe do some nappy free time at bathtime have a potty about read stories and let him see you using the loo.