I recently had some rough and hard sex with my boyfriend and now i can't feel my iud strings can they be there still i'm just scared that they went far up to were i can not feel the strings anymore?

See your GP or OB: Usual advice is that if you can't feel your IUD strings, then you need to see your FamilyDoc (GP) or OB. But given that this occurred after some fun times, wait a day or so (unless you report stomach/abdominal/pelvic pain) and chances are you'll find the strings again. I'd worry about dislodged IUD if you had pain. Without pain, IUD is most likely in place.