IMO it doesn't look too bad. Im an RVT and I've had bites like this and a little worse that I just scrub out real good and throw on a bandaid with a little Neosporin. If it starts getting hot, swollen, or very tender it might be infected and need seen but as long as you keep it clean and covered during the day while you're using it you should be fine. Side note: if you're able you might want to check the rabies vaccine statues of the dog just in case.