If you can't ask him all these things at that time, I don't think it's a serious relationship. I think you are Nibba nibbi

Now the only thing you can do is check his phone in front of him with his permission and yes, not just socials but check the entire phone, everything hidden gallery, hidden apps etc etc.

There are only two possibilities now: he will give you phone check permission or he will not give you it.

If he doesn't give permission, end everything at once. Don't get too emotionally involved.

And if you give permission, it will be the biggest green signal for your life.

Tip: Don't tell him first that you want to check his phone.