Why are you having unprotected sex? If you are 19, and clearly understand that having unprotected sex causes babies, then you should know the answer.
Did he come in you? Because of the times that you said yall had sex, whether he did or did not could have a lot to do with your outcome. Although it isn't very likely for women to get pregnant with just 'precum' a week or less after their period. But don't thank the stars because it happened to me. I miscarried 9 weeks into it. If he did come in you, than the chances of you being preggy are of course higher.
How long have you and your boyfriend been together? I am with mine for 1 year. I can understand that it just feels better for the both of you to not wear a condom. But bae, if you don't want to get preggy, don't do it. Are you on any birthcontrol? Have you missed your period? There is really no telling until you miss the first period after the unprotected sex. Girl, don't stress it, because that could definately stall your period from coming. Have you changed your sleeping/eating patterns? That could also delay your period. Im sorry that this is soooo long, i'm just trying to help. I know how it is for people not to listen to problems because we willingly had unprotected sex and should know the consiquences.Ya know?
Love always,
sarah!