Gosh I can't attest to the practices of every emergency clinic out there but what i have noticed is almost everything is disposable and not reusable. Maybe they swabbed the needle again to allay your anxiety. Did you see if it was removed from a wrapper or package beforehand? If anything maybe you could call and ask or simply go back and see what the process is so you can evaluate yourself what the risk is.
I would wonder more about tetanus but that is me.
Where do you live? The reason I ask is this, if you live in the United States or Canada or Western Europe or Australia or New Zealand, most likely the needle came from a sterilized package. If you live in Eastern Europe, the Middle East, Asia, Africa, or South America, then your chances of the needle being contaminated are greater. Sterile equipment is used in some places in those countries, but not always, especially in rural areas.
You said they brought the needle from a tray and then poured alcohol on it. That leads me to believe that the needle was perhaps just sitting on a tray and did not come from a sterilized package. Plus, if it had come from a sterilized package, there would be no need to pour alcohol over it.
In addition, pouring alcohol over an unsterilized needle will not kill the organisms that may be residing on or within the needle, especially if it had been used previously to stitch someone elses wound and had not been sterilized properly.
If I were you I would go to the clinic and find if they use clean needles (new, sterile needles in a package) or if the reuse needles. I would also find out exactly what procedure they use to clean their equipment and needles. They should be sterilizing everything with heat or with certain chemical solutions or both. Alcohol does not sterilize.
If you cannot find out how they clean their equipment, then you may need to get tested in about 3 months to see if you have been infected with Hepatitis B or C or HIV.
Best of luck.
I am from India. My concern is only regarding hep c. They said they use clean objects. But my concern is that if they used the same which was used on others. As i had asked them then they dropped 5-10 drop isopropyl alcohol on that and said it ok now. I am concerning so because there so many patients come. I searched over internet, somewhere i found isopropyl is not able to deactivate and somewhere i found it able and intermediate.