I need to know what blood marks frm a drug needle look like. If poss would like to see pics

I just need a basic description, or photos. Please, nothing overy gorey. No track marks, etc. Just would like to compare the strange little marks on my bathroom wall with something to try and find out what they are from. I suspect that they are needle marks from cleaning out a syringe, but I need to be as sure as possible. Thanks!