Do you guys also doubt everything you do?

Like I had to pay some bill on my Univeristy and I have been checking the account number five times now. Yesterday I was taking meds and instead of taking two pills 30 mg each i took 6 pills 10 mg each, same thing right? Well not to my f uped mind it isn't. I was checking it for 10 minutes and still was convinced I did it wrong, that I overdosed and will die in my sleep. I fucking hate how much I doubt in my own skills.