it is perfectly ok. there's no real difference between u or any other person, you just have to take care in not pricking yourself as any other one (it's not advisable to use a needle used on another person, not only for "safety" reasons which are present even on hiv- people, but also because of this http://1.bp.blogspot.com/-7g5KmqOZr2Q/UKrA9oiLraI/AAAAAAAAAEM/PR_sj7pAUQU/s400/syringe+under+microscope.jpg so the needle becomes more difficult and more painful to insert). btw, don't worry, you don't put your mother at risk in any way, it is full of hiv+ healthcare workers. in italy, for example, no one can be forced to declare its status by law because being hiv+, even for healthcare workers, it's not adding any risk for patients.
bye! sorry for my very bad english