Lower painful back/abdominal pains, Spotting for 6 days, headaches, feeling sick and bloated??

hi, quite embarrased bout this but im 17 and having painful/uncomfortable lower back and abdominal pains like as if im on my period which ent due till monday and sometimes little spasums in my stomach on the lower left, have had these pains for 2-3 dais an getting stronger. Feeling sick and bloated and have had my headache for neali a week it comes and goes weirdly. Have had bright red/pink spotting but only when i wipe after loo and have had this for about 6 dais on and off. Have been needin the loo more and sometimes instantly, my urine has been clearish with a weird odour not sore or anything tho. my moods have been a bit up n down and my breasts have been sore and look and feel a lil bigger, my breasts have been sore since the spotting. Have been waking up in my sleep n some nights im fine.
I did miss my pill tho (combined pill) on the 3rd of feb bcus i ran out, but had no problems with me missing it and took new pack as normal and on time, last time i missed it was bout 6 months ago and had a period 3 dais after i missed it which is ment to be normal if missed, but had nothing this time untill this which has bin going on for bout a week, and i dont think that all these symptoms is because i missed my pill 2 weeks ago.
What i think is that i might be pregnant or it might be something more serious :/ .

Please reply as i dont know if i should wait to see if i come on my period on mondai or just go straight to the doctors. :S

Thanks.

x