Had sex four days after , bleed for five day started with brown spotting later turn red for two days and the remaining two days brown ,is it implantation or period , i did both urine and blood pregnancy test weeks later all negative hope not pregnant?

Conception occurs within day or so of the sex. It takes about 3 weeks for the embryo to make enough HCG for a positive pregnancy test. Blood test may be done a day after a missed period. Home pregnancy tests should be done 4-5 days after the missed period. If the result is negative repeat the test in 4-5 days. Use first morning urine and follow instructions for the test carefully.