implantation bleeding or AF

So I have been TTC for 4 months now. Recently got off depo since May, I have had cycle since July. AF was suppose to arrive today and nothing just spotting. I put on panty liner this morning and I literally have had the same thin one on now for 12 hrs and just little drops. Doesn't look like AF with all the clots and stuff...I'm 18 days since my last AF... I wanna test but idk you think I should? I have had dizziness and nausea and headaches, fatigue like crazy but I know those are also signs of AF