I think I might be pregnant?

Okay so, I have always had an irregular cycle I got what I thought was my cycle 2 days ago but it turned out to be just a couple spots that were brown and light pick colored, it's been on and off since then. Now it stopped. I've been feeling really tired lately and had this feeling like I might get sick but I don't, I also have more veins showing in my breast and me feet and back are hurting and also fluttering and cramps. I took at test and it was negative could I be pregnant but just too early to get a positive?