Thought i have foreign body in my heel but ultrasound can't detect anything but suggest that i might be poked by some kind of small needle. at the time i got poked yesterday, i couldn't find any needle at all, no blood, no bleeding. am i at risk hiv?

If you are concerned, then get a test done. That is the only way to rule it out for sure. It could be the sensation in your heel was due to something else. But, a negative test would alleviate your anxiety. So, ask your doctor for an HIV test. Good luck!

No risk for HIV in such circumstances. Make sure you are up to date with your tetanus shot, watch the area until healed as superficial infections remain possible.