For most, as Ineligible points out there is almost zero percent chance of getting pregnant, but nothing in this life is 100% guaranteed, nomatter how unlikely.
I wouldn't recommend getting a morning after pill though, because if you've not missed one, then the morning after pill would just mess your cycle up, and there's no reason to get it unless you have massive doubts about if you've taken your pill right, which you don't appear to.
Sometimes, I guess the first times, the first coupla months when you're on the pill, maybe you just don't feel it's safe, because you're not used to it, and it's not a barrier method, I can understand your stress, however you should trust in your medication... the doctors will have done all the appropriate tests to have given you the right kind of pill, and the right dosage, so I wouldn't worry about it... yes, of course they can be wrong, but so can everyone sometimes, and the likelyhood of them having made a mistake is rather low... after all, there is only one woman who I have ever known who has gotten pregnant whilst on the pill and taking it correctly.
You'll see after a month or two, as long as you take your pill properly and at the right times and everything, you will almost certainly be fine
"Words have the power to both destroy and heal. When words are both true and kind, they can change our world." -- Buddha