Walmart tests

Is 9-11dpo/ 4 days before missed period possibly too early to get a BFP on the Walmart cheapie tests? I took one this morning and it looked negative. I have been having weird cramps for the past 3 days and had some bad lower back pain about 2 days ago. Usually I would have period cramps by now (ones I feel down in my vagina) but I don't. Hoping they stay away and this other cramping is a good sign! Just making sure I'm not out yet. Let me know your opinion. Thank you!!