feeling very stupid, main dealer tail of woe..

[dfen5]

just bought a used car from a main dealer. specifically asked about the main dealer service history, when it's next due and so on. Even my old Avensis, I still got serviced at Toyota, just one of my things.

salesman said next service in about 20k or two years, car will show when, driving style depending, flashed the service book but said it's no longer stamped, all electronic records to stop fraudulent books etc. big check list carried out etc.

got the car home and started browsing through the books. found the service book has been stamped, only once by main dealer in 50k (current mileage) at 37k. other services at joe bloggs garage at 15k with boxes incorrectly checked and a 'small' service at a local garage at 47k. service history print out shows the one MD service.

Feeling pretty stupid now, and to be honest, absolutely furious at the deceipt. much as i like the car, i really want to return it. no MD history to me devalues the car and I'm concerned about potential failures coming, especially seeing the obvious service items checked that don't relate to this model. Am i being petty ot am i right?