need advice

I had a surgical abortion 8 weeks ago and got the implant put in the same day. I was 8 weeks when I had the abortion. I didn't bleed after the abortion and I haven't had a period either. I've had a scan and they said the pregnancy isn't carrying on and that it's gone. However since then, I've had unprotected sex once, about 2/3 weeks after (no condom, but obviously protected with implant) And I've been getting pregnancy symptoms.