After a quick buzz with the clippers it was revealed there was no puncture wounds or abcess (thank god), but Zack has a really bad "hot spot", poor boy. I felt awful I didn't see it before but under the thick fur I couldn't tell.
I was surprised he has a hot spot as I haven't seem him scratching there but now the air can get to it hopefully it will dry up and heal.
I hope it is just a one off and not the start of any allergies or something that I know alot of terriers can suffer with. I have kept Zack on Omega Pro 3 supplement for the past year to help his skin and coat, so I am keeping my fingers crossed.
Zack was sent home with antibiotics for a week and I am to use polysporin and keep the area clean.
Hopefully he won't have to wear the dreaded E-Collar, but if he starts to scratch now the hair has been clipped and it is more exposed, then we may have to resort to wearing one for his own sake until his hot spot heals. Finger crossed it won't come to that.
Luckily Zack's vet is my friend so I know he is in good hands.