Could I be pregnant? ?

Well my bf came back from the army on the 10th same day that I should gave ovulated well seen as he's in the army we only did it that weekend and now I'm wondering if I'm pregnant I feel realllllly sick, hardly have an appetite, dizzy, lower backache, and have bad cramps and pinchy feelings (which I don't have even when im on my period there only mild) headaches, at one point I had a burning sensation in my lower back then in my bum cheeks and then yesterday it was in my neck. Tmi lol I don't know whether yesterday I had implantation bleeding they looked like tiny needle pin pricks hardly noticeable (i dunno whether it was already on the paper) and I took a test today probs too early but it was a bfn :/ I'm feeling sick almost all day I have a test spare and I'm gonna try again on Saturday at 15 dpo (I also had a really bad cold fri night and all day sat and it should last alot longer as it was so bad but everything I'm experiencing is really weird please leave your opinions