Is It Just Branding?

I had a headache yesterday.  A few days ago I decided that I will not take another medicine for headache because I have regular bouts of migraine and I fear for my kidney (although I'm not sure if the medicine will have an effect on it).  However, I decided to take one yesterday even if I only had a slight headache because I had class at night and I wanted to be sure it does not turn severe.  I went down at Buendia and saw a Generics Pharmacy store.  I decided to check it out and maybe buy from them because their ads say that they work as well as their branded counterparts but cost very cheap.  I went inside and asked how much is the Mefenamic Acid.  The sales lady said P2.00!  I must have been shocked because I suddenly blurted out "Does it work like Dolfenal or Ponstan?  It does not have any side effects?"  I hope I did not offend her.  Anyway she said yes and I stammered while telling her how many I wanted to buy.  I was saying units in pieces but in my mind I was thinking of buying one banig.  I finally decided to buy 3 pieces.  This is what they gave me: