Ordinary Punjabi speech now contains a very large amount of English, and not only technical vocabulary: the connectives, the discourse markers and whole clauses.
In the diaspora this goes further. British and Canadian Punjabi runs the two languages together with Punjabi grammar and English content words, and the result is intelligible to another diaspora Punjabi and confusing to someone from a village.
In Punjab itself, English is the aspiration and the medium of the private schools, and a great many children are being educated in an English their teachers do not speak well and are losing the Punjabi they do.
The result described by teachers is a generation fluent in neither, which is a claim made often and measured rarely.
Punjabi popular music mixes the two deliberately and successfully, which is the one place where the mixture is an achievement rather than a loss.
Languages take from each other constantly and it is not a problem in itself. It becomes one when the borrowing runs one way and the borrowing language is not being written.
Punjabi has absorbed English wholesale: the vocabulary of school, of government, of medicine, of the visa office and of the phone is largely English in a Punjabi frame.
Code switching mid sentence is normal and is not a marker of class in the way it is in some other Indian languages. A farmer and a professor both do it.
The concern about it is really a concern about domain loss. A language that keeps the kitchen and loses the office is on a path that has been described many times elsewhere.