if my nitro rc car is not broke in right will it ever run right

Maybe, maybe not.
It really depends on how badly it was broken in. If it was started and ran right away (never had a real break-in) then that will - at a minimum - shorten the life of the engine. If it was badly overheated during the first few tanks then serious damage could have been done and it may never run right.
On the other hand, if a decent - but rushed - break-in was done then it will probably have a shorter than normal life but will probably run fine in the meantime.