I feel so sad... can you please read and give me your insight?

I am feeling very sad and I just want to cry... Maybe I am stressed, I don't know. My last period was on July 12th and I have taken four HPT's all that have came out negative. Two were dollar tree brand and the other two were EPT Certainty Digital tests. My feel heavy when I lean over and it is hard to get comfy when I am bed, which is where I am until I have to go to work because I feel so sad and tired. I keep having discharge (clear/whitish) and think it is my period but it isn't. I should probably go have a blood test done that way if it is negative I can get this thought of possibly being pregnant out of my head. What do you ladies think?