Can I use these both interchangeably?
Person A. - Tomorrow, I want to introduce you to my parents.

If I say;
What if they didn't like me?
What if they don''t like me?

Question

Can I use these both interchangeably?
Person A.  - Tomorrow, I want to introduce you to my parents.

If I say;
What if they didn't like me?
What if they don''t like me?

Answer

'What if they don't like me?' - this is the correct one as it uses the future conditional 
'What if they didn't like me?' - implies that you've already met them and are referring to the event in the past