Hello, since January my cycle has been shorter by about 5 days. Am 17 yrs old. My first period this year was on 1st Jan after counting 27 days. That was normal. On 7th Jan (day 7 of my cycle) I had anal sex with my boyfriend and various forms of foreplay (but not intercourse). I was expecting my period on 27/28th of Jan but it came on 23rd. It was lighter than usual too and lasted 4/5 days. To confirm that it wasn't implantation bleeding I have done 3 urine tests more than 2 weeks after my abnormal period that turned all negative. So my Jan cycle was 22 days. It has been another 22 days since 23rd Jan and I think am on my period again. Today is 15th February and is day one. I had cramping and clear mucus discharge with a bit of pink blood and tissue fragments. Is it normal for day one?