Regarding name change in educational mark sheet and certificates.

I have my name in my educational certificates as, say "John", but in my other document like Aadhar, PAN, Bank Account Passbook etc, it is like "John Smith". I want to know whether I should go through the painful process of converting my name in my educational certificate to "John Smith" or to change it to "John" in other documents as well, or I can keep it as it is. I know that not using a surname causes troubles while filling the form which make it compulsory, so I actually want to keep my name as it is in educational certificates as well as in my other identity document. Is such a discrepancy of "absence of last name" in educational document bearable? I specifically want to know if I can face problem in getting passport etc?