He is not angry, he is worried. When he was acting lovey-dovey, the moment was killed by the phone call, that too from Akki. And Priya's talk with her father makes him think that Priya will leave him for Akki. Bandha tension mein hai aur is liye angry hai
He should have just sung - Sallu wallah song
Janam samjha karo, Janam samjha karo
As mentioned earlier, Priya knows. She will get her dad behind bars. And that will cause Ram to realize that there must be some truth to why Priya is supporting Akki