Men of India what do you do to make yourself feel masculine?

Today something stupid happened. I have injured my knee and had gone out to buy some food. I was sitting on a stool in front of the shop when three typical "Delhi ke launde" types came there and ordered some stuff. One of them turned towards me and putting his hand on my shoulder said in a mocking tone "Chal beta uth ab, bahot baith liya" or something like that. I hadn't even looked at him but I actually stood up cus mentally I was thinking about standing up only as my leg was paining and the food was ready. However this made me realize that I lack assertiveness completely and I should have continued sitting there as there were already four chairs present. On top of that I am 20 and they were 18-20 years too. I am an introvert and don't like getting involved in quarrels irl. Has this happened to anyone here? What do you do in such cases?