Advice please ladies

So... Me & my other half had sex on my 3 most fertile days (30th, 31st & 1st) and today I woke up with weird sharp pains/cramps around my lower stomach area... Would it be too soon for implantation pains? How long does it take for implantation to happen? I was on the implant for 6months & had it removed Christmas eve... My periods started off as every 2wks, for 3-4days... Since April they have got more regular & my last one was exactly 28 days & lasted 4days which is normal for me. We have been trying religiously for months & had no luck. Someone send me some baby dust please!!! xx