HELP!! ADVICE??

Here lately I haven't been feeling like myself. I get real bad headaches, dizziness and I have this lower back pain that feel like pressure on my tailbone and moves. after my ovulation day I was a week late but then my period was short and not heavy like usual.. I had a faint positive but tested again after and negative. is it time for a doctor's visit and blood test? or am I losing my mind?