What Causes A Person To Panic And Repeatedly Check The Things?

hi i think i have ocd,i just read some info and there was a qwoute saying that a person had to keep cheacking things where of and that there number was 3 and that they had to do things to that number like washing things and that some time if they didnt do somthing with the number that somthing bad will happen but with me its like i turn my hair straghtners of and i no i have turned em off but i keep going back to make sure i do this about 5-9 times befor i can walk away then sometimes when i get so fed up i say to my self if u go back then they will be on and they will set a fire then i will leave my house and i will keep cheacking i locked my door then i get fed up and i say if i go back and cheack then my house will get broke into then i get far away and i think to my self did i leave the door open then i start panicing and i think say that my house will get broke into becasue i didnt lock the door and my way of trying to say it wont happen is for me to tap my head 4 times and i set my alam to get me up but i set it like 10 times so if i put it on 10.06 then i change it and say no it cant be on that number it has to be a number above or below that number rather 5 or 7