Dont know what to do

Im unsure what to do anymore. Alpt.of headaches, back pain, really tired, burpy amd gassy, and ive been javimg nausea once in awhile. Hasnt been too constant but this morning I woke up with it again. Ive taken several first response pregnancy test and they all came back negative. Monday was 4 weeks since I last bled and I haven't had any signs of any sort to know that my period is coming on. Ive also been having a lot of hot flashes. Should I keep waiting and see what happens or what should I do?