Speech delay and response issue. Me.

My son is 26 months old. He is an active kid who observe things closely and has good memory. He is able to communicate whatever he needed only through his actions. He blabbers a lot and say mummy, mamma baba, bai 1 to 10 and few of albhabets. He responds to his name in 2 times. However, still he doesn't speak, or doesn't look at us when we talk to him. He don't have a hearing issue coz he can hear if mobile ringing or bike/card sound from the road and run to see the car/bike. He tries to immitate the cartoons and the way they speak in cartoon but he just but can't speak a sentence or a meaningful word. He starts crying if someone comes at home and he doesn't like anyone apart from family member. Now everyone has started suggesting me to do a check up foe him related to neuro. I am so scared, please guide me.