What are the signs of pregnancy?

I have a question for the moms that may have had similar issues. Back in February I had a possible early miscarriage, my gynecologist isn’t exactly sure as I wasn’t able to see her until 2 weeks after the miscarriage. Well ever since when my periods start I’ll just spot for 7 to 10 days (use to bleed pretty heavy and have cramps for 6 days). It’ll be a mixture of pink, red and brown blood and I only have to wear a panty liner. Well I had my “period” on the 9th this month, then started spotting again on the 24th and it was a mixture of brown and pink blood for 4 days. My nipples had been getting pins and needles in them, and hurting. Saturday my left boob was swollen and tender and had a hard knot below the nipple, the swelling, tenderness and the knot is gone in my boob now but my nips keep cramping and getting this burning pins and needles sensation randomly throughout the day. I took a pregnancy test and it was negative. Has anyone experienced this before? Could my hormones be out of wack? Im gonna be 23 in 2 months if that makes a difference.