Day-after pill made my period 10days late, then got my next period regularly after 28days. before first mentioned period i had 2 negative pregnancy tests. can my period be implantation spotting, i usually have light flow only needing a pad for 2days?

Implantation bleeding is usually spotting not requiring pads. If you had sex since your last period, do a home pregnancy test, if you miss your period by4-5 days. If the result is negative repeat the test in 4-5 days. Use first morning urine and follow instructions for the test carefully. If you do not wish to be pregnant, use contraception all the time, every time.