Blood at 4 weeks preggy

I am 4weeks into being preggers now. Just 1 hour ago, i came back from work & peed and some 2drops of brown blood followed , then i put on my panty & it stains as picture. Now im having panty liner and i have few more, but no painful cramps like menstruation, just tiny pain at lower abdomen. just generally, i feel emotional, and really just want to cry all the time right now. Please advise if this is normal. As this is my 1st pregnancy experience