I just had light pink/brownish spotting for about 2 days that just stopped without a flow following, could this be implantation bleeding? i had sex about 2 weeks ago?

Could be: 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.