Is something still wrong with our AC system?

So our friend came over to look at our AC system (he works in commercial AC) bc it wasnt cooling to house. He tried a bunch of things and ultimately gave it some gas and told DH to power wash it and hopefully that would work.

So the next day DH borrowed a power washer and did so, that night the AC worked fine (set to 75), next night worked fine. Yesterday when I got home AC was set to 75 but house was at 78 and wouldn't cool past 78. We set it to 72 and woke up with it at 72.

Is this normal? is it bc it was so hot and it took a long time to cool? I should probably have an AC company come look, right?

Re: Is something still wrong with our AC system?

I'd have a company come to check. Sounds like a freon leak maybe.