It does look like ich. Spot on the pec fin, for sure. If so, you have to treat until there is no sign of it for at least four days. Read up on ick.. the parasite is only vulnerable to treatment when free swimming. That's after it drops off the fish and develops from that stage into the free swimmer, which goes looking for a host.
Salt works very well to kill ich, raise temp to 80, use salt, should work. There is a strain of super ick around now that can take much longer to resolve, but hopefully this is not that one. Just like super bacteria.. some of them have become resistant to some of the meds used to control it. Best to use salt, it's less costly and effective.
The 'skeptical aquarist' is a great site for info that is reliable on many topics, including this one.