Confused if I'm pregnant or not?

My belly goes hard and I have a bump figure (small) I often feel bubbles in my belly, I always have back ache, sore breast? And feel sick.. I bleed but a light amount I would class as spotting? However I'm only 15 years old. I can't speak to my mum or dad as I don't have a close relationship with them? I'm scared! Please give me some advice ..