Period symptoms vs Pregnancy symptoms

Okay so my period has always been irregular because I have PCOS but I still keep track of it as best as I can. My period in February was Feb 21 and ended on Feb 26. I last had intercourse on March 4 but I was reading that women can still have their period while pregnant. This morning, I woke up to find a dark brown color instead of red. Then throughout the hour, it was more brownish pink but now it just looks like a regular period even though I'm experiencing all forms of symptoms like tiredness, tingly feeling in my breasts, especially around my nipples (almost like an itching burning sensation) my WHOLE stomach feels just totally bloated which is normal when I get my period but its like extreme. I also have intense lower back pain which again, I'm used to but this time its REALLY bad, worse than usual. I can't tell if this is my actual period or spotting. The blood is much darker than it was this morning and its not really clotting much, a tiny bit but not a lot. Is it too soon to take a test? I've heard from a few people that it's way too soon and I've heard from others that you can take one 14 days after sex or after ovulation but since my period is irregular, I wasn't sure when my ovulation would be happening. 

Any answers right now would be GREAT. Thank you =)