Turbo having issue

I went to long distance this last staurday so while returning my car bump in huge pond and my oil tank broken,so I replaced the oil tank new with the help of local garrige person ,after replacing it my car gives the whistle sound from engine while accelerating. also the pick up has down mariginally.

so that local garrige guy told me that the turbo has been malfunctioned,is this true,if yes how can I go further where I can do this repair.

I ma living in pune city will you please suugest