Offer negotiation help

I cleared the interview process and HR confirmed the numbers over call. I was expecting 20 LPA in hand and he offered 18.5 + 2 Lpa as a retention bonus. I renegotiated and asked if he could make it 20 + 2 as a retention bonus. And I'll join in a week. He said he will mail the offer intent but haven't received any mail yet. When I called him, he said internal discussion is going on, he'll inform me as soon as there's any update. It might take 1 or 2 days.

Now, I think that they are interviewing other candidates and might revoke the offer.

What should I do? Should I call and tell him that I'm happy with the original offer? I'm really panicked right now🥺🥺