HELP! Tubal pregnancy? Pretty lengthy

I just left an appointment. I had some minor/major cramps on Wednesday or last week for about 3 days that were on my left side. I had my last day of my fertile window the day before this happened.. And I did have intercourse 4 times during this window. (The first day... & the last three days) I was reading online about the cramps and they said possible implantation cramps but also possible cyst cramp.. It became so bad I had to go to the ER but they took blood and urine and got a negative test and also no signs of infections or anything unusual. They did not give me a ultrasound due to the tech already being gone. So they suggested I call my OB/GYN to get seen by her. Well I went today and see the nurse practioner because my Dr was on Vaca'. And she told me I could have possibly have an tubal pregnancy if the pain comes back but she didn't give me and ultrasound for cyst because I wasn't in pain. Well once she pushed on my belly I started to cramp but it's stopped now. All the pain is on my left side. I'm not on BC and I also have a one year old! I'm actually TTC. Could this actually be implantation that happened? I have my period coming in 7 days and it feels like the longest 7 days of my life.. Sorry this is so long. But can anyone help me.. Has anybody been told this. Has anyone had this? I'm so confused.. Anxious... And scared all in one.