My last period was on feb 12 after the previous on january 1st.my bf ejaculated on my vagina after an oral sex on the 23rd of feb.i washed that off 3mins after.i have been having this headache continuously for a week now,back ache,constipation,once in a while heartburn,abdominal pain,no period yet,sleepless nyts too.took a home pg test last week but it came out negative,havent seen any blood yet.please am i pregnant?i need help!also is there always an implantation bleeding in every pregnancy?