pregnant with iud??

So i have a copper iud. I got it about 3 or 4 months ago. I have been bleeding since September 7th. About 5ish days ago I noticed that my iud strings looked a lot longer. I made an appointment and they said that everything looks normal and she just trimmed the strings.I’m worried it could have moved or something? I had unprotected sex on the 15th and had a constant heavy flow of blood up till today. It’s lighter and not as heavy as it was yesterday. I’m a little scared i’m pregnant or am experiencing implantation. any ideas??

update- i quit bleeding about an hour ago. so confusing.