First up, lab techs work inside a laboratory to process samples extracted from human body for medical investigation. You mean the phlebotomist had come for your blood sample collection.
Secondly, there is no reason for you to believe there could be contamination or harm intended because there wasn't one. These are professionals that are trained to take care of patients health and safety.
Please see a counselor if you have anxiety during such events. Not an HIV concern, testing is not recommended for this event.
Next time someone does blood work tell them in advance that you worry about disease transmission, then they will show you that there is no risk. THat way you won't have to spend time worrying about things that you imagine have happened.
You should forget about this event and anything like it, and potentially seek therapy if you are inventing irrational scenarios like this.
Needles are not re-used, and clean needles are not mixed in with dirty needles. Not ever.
Even if this DID happen - and it did not - a blood draw is not a risk for HIV since blood is being taken out of you, not injected into you, and any virus that was on the needle would have been exposed to the environment, instantly rendering it unable to infect. There is no "what if" that you could add to this imaginary event that would make it a risk for HIV.