Handmade play changing

Is there a smaller iv needle that is allowed to handle medicine than the pink one? - needle medicine

I kept sticking straight into the artery. say it is the smallest needle possible to manipulate the drug, (iv needle pink), but I wonder why. What baby? Did they stick needles baby too big?
I am still bleeding and bruising after a big .... iv I hate how it looks and feels and want a smaller needle!

I'm clinging to false hope or is there a smaller one for use by an adult?