Recording Phone Call Without Permission In Criminal Case Id Legal ?

A & B had a fight, A injures B seriously. B files FIR against A. Now A calls C(who is son of B) for settlement. C replies his call saying "you hit my father like you were going to kill him", C also says "you were having knife in your right hand" etc. After call ends A gets feared that why C was saying abt knife, which A don't knw. A thinks that C might be recording his call and trying to make him confess some false things too. So my question is, whether C did right or he is guilty for recording call without consent. And also can those reocrdings will be valid against A or not?