TTC for a year and a half

Sue
Hi! We are trying to conceive for 1 1/2 years now, we tried on the 9th of my peak,did everything to keep it there, cramps for almost 1 1/2 weeks thinking ill probably be having implantation bleeding but nothing happened, checked today the 24(1st day of supposed period) pregnancy test came out negative.. Can i still be pregnant? Pls advice.. Thank you in advance