Hi Ive Been Getting Some Mysterious Bug Bits Every Since

Hi ive been getting some mysterious bug bits every since i went over someones house and got bitten. Ive not since been over there but new bites continue to appear. Today I actually saw something it was a small yellow bug that looked like a mustard seed. I immediately took a shower washed clothes and still saw one. i killed it freaked out and took another on then the itching stopped. Now I have new bites. I would love to send pictures so i can know what I am dealing with.