Could i be pregnant?

I had sex twice about 2 weeks ago with a condom on my ovulation week and once a few days ago, only this time without a condom and it was only in for about 4 seconds as we realised what we were doing.

In the past few days i have been feeling sick contantly and vomited once, i have backpain,the rare headache and am constantly tired, aswell as having white discharge every day.

My period isnt due to start until Saturday 23rd.

Should i be worried?

My main problem is.. im 14