reverted potty problems w/4 yr old

My son is 4 (since october) and was doing fantastic until a couple of weeks ago. Now he hardly ever uses the toilet. He keeps going in his underwear and I don't know what to do about it. HELP!!! I have taken away his game-tab and keep a close eye on him for signs that he has to go or that he has gone in his pants. If I ask him if he has to go he always says no, and if I ask if he has gone, he says no. I do not know what else to do. He has both a child's potty and also uses the regular potty. I take him to the potty and make him sit on it just in case but he still doesn't use it.

What I've heard of parents doing in similar situations is set a timer, maybe for every 45m-1hr. Tell him ' when the timer goes off you will go potty, even if you just try.' Don't argue or make it a power struggle just say its time to go potty. You can return to doing x activity after you go potty. Stick with it!

Quoting mamato1boy1girl:" What I've heard of parents doing in similar situations is set a timer, maybe for every 45m-1hr. Tell ... [snip!] ... make it a power struggle just say its time to go potty. You can return to doing x activity after you go potty. Stick with it!"

So it's like starting all over again? Okay. I am so uncomfortable being pregnant right now that it hurts for me to have to "take" him to the bathroom when he doesn't want to go. ( I am not with his father and my SO is not going to be home for a couple of months) But I will do what I have to in order to correct this issue. Any ideas why this is happening?

My 3yr old son is doing the same thing, except he only does it with his dad and i and my other family, hes fine and goes on his own. I have no clue what to do

I was reading it could be a power struggle. Also it could be due to constipation.. I suppose I'll just try taking him every hour just in case.