Needing some advice

The last few days have been blahhhh. I've been feeling nauseas, been getting headaches and moderate cramps, today I started getting back pain and tender breasts. and the last three days I've been spotting very lightly, and usually my period is heavy. I'm on contraception and have been for awhile (4-5months) now but is it possible I could be pregnant? I'm 17 live with my Dad and Partner but I don't have a mother figure to talk to about this kind of stuff. Please be kind with your words I'm only seeking advice.