hi ok a thing to remember is have you had any spotting its a sign that you could be pregnant around implantation day? and that it takes male sperm around 3 days to get into place to either receive your egg or make an egg there fertile. so you really need to be having unprotected sex around 3 to 4 days before your ovulation day this means his guys are there in place and waiting for your egg its ok some go left and some go right and can live for around 7 days inside you. do hope this helps you. good luck
could i feel implantation 2 days after unprotected sex if we did this slightly post forecast fertile days? . i thought my chance was out the window according to when i was most fertile. but my husband and i decided to start trying anyway. we had unprotected sex on may 19 2015 and then some dull throbbing on my right side (uterus) and terrible lower back pain on same side starting last night (may 20th) and continuing into today (may 21st). my fertile calendar said i was most fertile from may 11 through 16 with peak at 14th. but my cycles are about 31 days vs. 28.