i have been on birth control for 5 yrs and quit taking on 1/8/13. kay so my last period was 1/4/13 to 1/9/13. then i have had sex the 17th 20th 24th 25th 26th. unprotected mostly. and i have since those just dont remember exactly what days. i have now completely missed my period. i have had some brest tenderness, not feeling good, being tired, and about 2 weeks ago i had some spotting. which is odd for me. i have took 2 hpt and they both have been negative. should i be worried or have blood work done?