Should i take a pregnancy test? :(?

well I've been feeling dodgy all this week its headache galore! and i feel nauseated like alot! and the most random smells and foods make me begin to feel sick (daft things like the smell of mr sheen polish and taste of celery) i'm usually quite keen on my food but now even thinking about it i can't be bothered because i get dizzy standing up, i've been feeling the heat alot more too! the only thing making me doubt is that the last time i had was about a month ago and i got spotting for two days(which i NEVER get) and then my period came the day after and i thought oh okaii fine but I've not had this cycle at all...and now i'm really confused and don't know whether i should take a test or if i can i've counted now that i'm around 5-6 weeks if i am preg advice please? x x :) cheers pplz x