You Do Need power plug adapter while traveling from Serbia to Trinidad & Tobago.

Here is Why You Need An Adapter

The outlet and plug type used in Trinidad & Tobago are A and B and in Serbia are C and F. This is how they look like.

Serbia

In Serbia, outlets of type C and F are in use.

Type C

Type F

Trinidad & Tobago

In Trinidad & Tobago, outlets of type A and B are in use.

Type A

Type B