brown spotting on my underwear

Mai
Hey guys so I need some advice, I thought I'd be getting my period this week because I sort of got the signs and my period is irregular sometimes but 
I've been having this brown spotting on my pad (wore one just in case) and now I had to go bathroom and pee and my underwear was blue so I thought that was blood but then when I wiped it off it was a browny colour spot
And the brown spotting is kinda like when you finishing your period that's what you get then but there's no blood period or anything 
Can someone please help me out and let me know what's happening xx