What are the behavioral manifestations of people with OCD?

When crossing the street, think of rushing to a passing car, etc. There are often opposites that go against one's heart's will.

Fear that you will hurt others, worry that you will say the wrong thing, worry that you will be contaminated with poisons or attack by bacteria, etc.

Obsessions, which manifest as recurrent and persistent thoughts, thoughts, impressions, or impulsive thoughts.

Personally, I mainly show it when playing games, like Plants vs. Zombies, each row must be the same, the nuts are gnawed and you have to change one, or this row is planted with man-eating flowers, then each row must be planted with man-eating flowers (whether he is useful or not), otherwise it looks unpleasant, and playing minecraft is also, when building a house, it must be symmetrical and left-right, otherwise it will collapse.

Repeating some actions, knowing that they are unnecessary and not being able to get rid of them.

Double-check that the doors and windows are closed, and double-check the contents of the letter when sending the letter to see if there are any typos, etc.

Repeated memories of past experiences and past events are meaningless, but they always linger in my mind.

Whenever I talk to my boyfriend, his obsessive-compulsive disorder conjures up unpleasant or ominous situations.

Very perfectionist, compulsion is more terrible than depression! There are many symptoms that ordinary people really don't understand and think it's ridiculous!

I walk the stairs with two feet must be average, if the right foot takes an extra step, then the left foot must be made up, as for how to make it back, is to walk the stairs with the left foot on the flat ground two times, which is equal to make up for it, it feels very average, is it sick, me