Late Talker

My 1 year and 8 months old daughter still not saying any word. She talks naman but you cannot understand any single word except for Mama... She can follow simple instructions/commands like "get that...", "you kiss Mom", "put the cap on your bottle" etc. She bang her head on the floor or wall, maybe out of frustration kasi nga we cannot understand her tantrums especially if she want something... Parang she cannot express herself. I read kasi her age daw normal naman nag bbang ng head (not repeatedly) lalo na for baby na late magsalita. When she wants milk naman, she will only point it using hand gestures.. I would ask her, you want MILK?? and I will repeat it 5x to think she will copy the word MILK... Do you experience this Mommies and Daddies??? Me and my husband is planning to have her check baka delay lang talaga or something... She looks completely normal, mentally normal...