If my urinalysis came back with sperm cells: absent, does this mean im not pregnant? or i just have no sperm cells because im female?

Means nothing: It simply means you either had not had intercourse recently, or that if you had, that none of the sperms were contaminating the urine. Even if you had just had unprotected intercourse with a fertile man and there was sperm in your vagina, if you gave a clean-catch sample, you wouldn't have sperms in it. Testing for pregnancy nowadays is reliable. I hope whatever result you get is good news.