If someone blocks you on WhatsApp and you're not sure if he/she has really blocked you or not. Then in this post you'll find out how you can find out if someone has blocked you.
Step 1:- Click on the menu (3 dots at the top right hand corner).
Step 2:- Select New group and add that person in the group.
Step 3:- Give the group a name and you can see the group has been created. If you see an error message and can't add the person that means that person has blocked you.
Step 4:- If you want to be sure then click on the menu button (3 dots at the top right hand corner).
Step 5:- Click on the group info. Then click on the add participant.
Step 6:- Try to add the person. If you still can't add the person then you will know for sure that the person has really blocked you.
Note: One thing keep in mind that if the person unblocks you again after some time he/she won't be able to see the messages you've sent in-between the he/she blocked time.