Very unsure am i pregnant ?

Hi there just looking for any little bit of advice here I am nearly 23 and (F) and i am unsure if Im pregnant, for the last month on and off I've been kind of queasy not every morning just some have felt dizzy but not alot I don't have sore breasts but they have felt itchy today i have also had slight cold symptoms e.g runny nose and sneezing but never seems to come to a full cold and this week Ive had notions to eat omelette and fried onions (I have never ever liked either) the only one time I have had unprotected sex (well he pulled out) was around 5 weeks ago. My period was due on the 24th of january but I woke up on the 20th with pains in my stomach kind of like period cramps but was also round my lower back I went the the loo and when I wiped it was as if there was blood but very water kind of pink then I got light brownish discharge for about a day and then it was gone I'm usually quite heavy. Im very confused as I thought this was a period but as I've said above my symptoms persist.