17, pregnant? Need advice

On the 10/3/2016 I stopped taking my pill, I had a period at this time too, that period started on the 7th, then on the 21st I had unprotected sex twice, and again the next day, but with a 'pull out' method, no cleaning in between though just wiping off what was on me, I suppousibly ovulated around the 20th-22nd which was when this sex occurred, I took no notice to any of it at all until yesterday which would have been 13 days post sex on the 21st I noticed I keep getting super light headed and dizzy out of no where, my nipples are killing me, I noticed a weird crampy feeling in my uterus I could legit feel my uterus and a pain in the left ovary, I went toilet at 11dpo and when I wiped there was a tinge of watery blood and it's coming from where a period should come from but it wasn't my period as it hasn't kept bleeding it has just stopped after that, I'm not 100% sure on what to think or do, any advice would be so helpful! Never usually receive any symptoms of an oncoming period, I have been super tired and sleeping every chance I get since about 10dpo, feeling nausea for a little after eating a meal and not being able to finish meals, my nipples are so sensitive the slightest touch to them hurts! I'm 17 turning 18 and need some advice!!! 
I had no symptoms until 10dpo. 
Unknown I have to take a test but I'm just not sure