RPM became too high after engine tuning

Hi Sir,

I do routine car checkup form Toyota service center, but after my recent engine tuning service which involves most importantly
1. Throttle cleanup,
2. Spark plugs cleaning,
3. Resetting fuse from fuse box at the end

after I started the engine I felt a high rpm as my engine sounds a bit high than normal, I inquired the mechanic but he says it will get normal in an hour or two as it happens after every tune up service.

I did not notice any such thing before with engine tuning service so I put a complaint against them but all in vain.

Now I have changed my oil, oil filter, air filter but still I feel that my car is driving a bit harder than before as my car runs / drives very smoothly after engine tuning and changing oil, oil filter, air filter.

Can you guys give me an expert opinion in this regard.