I'm assuming you didn't take the morning after pill.
Nausea, dizziness, headaches and mood swings are also signs of PMS. Food aversions can come from a cold or flu. There's certainly a possibility of pregnancy but you really can't go on symptoms alone, especially before you miss a period. The stress from knowing you had a condom mishap can also mess with your body and cause all sorts of symptoms, including a missed period.
I do think you need to take a pregnancy test. For the most accurate results, you should wait till your period is actually due, or even a couple days later. Home tests should always be done first thing in the morning when you get up. That's when your hormones are strongest and your urine should be more concentrated if you've slept all night. Also, false negatives are relatively common; if you get a negative result and aren't convinced, wait up to a week and check again. Good luck!