if your worried about the cost of home pregnancy kits, they do mini packs of 2 in poundland- i doubt they're 100% reliable, but im sure they can fill the gap till you get round to buying a proper one :) good luck! :S
A home pregnancy test should be accurate if taken at least 2 weeks after having sex and use it with first morning urine. The only way to know if you are pregnant or not is by the pregnancy test. Symptoms and anything else is unreliable.
wait a couple of weeks and take a home pregnancy test. If you test now you might get a false negative because it is too soon to tell.
Wait till your missed period