Help! 13 month old gags on textures

April

So I feed my 13 month old solids. He used to eat completely mashed bananas and avocados fine but now gags on them. He gags on yogurt and a thick lentil soup I make. He still beast feeds and never took a bottle even though I tries so much. He even gags on whole milk in a straw cup. I have tried giving him apples and oranges, mashed between my fingers and he tolerates them as long as they are tiny bites. I tried to give him bits of watermelon the other day, again pinched between my fingers but he gagged and threw up everything. All he has had since morning (it is now 6 in the evening) is a bowl of yogurt Why is he so sensitive to textures? I am so worried. What do I do? How do ai get past this? Thanks!