Yes, there could still be pre-ejaculate.
Once you have a missed or late period, you can be sure of the results of a home pregnancy test. It takes mere minutes to see the results. As far as which scenario posts the higher risk, it is impossible to say because 1) you say you do not know if the condom broke or tore in the first case, 2) you say you have been taking your pills erratically (which, btw, means you should basically consider them ineffective) and 3) we do not know when -- or if, given the pill -- you ovulate and are most fertile.
More importantly for everyone involved is your STD and STI risks. That isn't to say pregnancy is not important, but in people under 22, statistically, far MORE of you transmit or contract STDs or STIs than those who become pregnant.
So, don't blow off that testing, by many means, as you had no protection form that whatsoever in the last incident. I'd suggest you see your GYN as soon as possible for a full screening.
I'd also suggest you take some time to think about all of this: are you ready for it? And when I say that I mean, can you practice both safer sex and responsible birth control every time? If not, it may just be more than you can handle right now, and it's generally safe to say most sex isn't worth getting an STD/STI or acceidental pregnancy for.
Editor and Founder, Scarleteen
My epitaph should read: "She worked herself into this ground."
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