I'm sure your peaches will be fine, especially if you had advice from your Mom.
When I do peaches, I don't even boil up a sugar syrup--I just stuff a quart/litre jar full of peach halves or quarters, dump in half a cup of sugar when I get the jar half full of fruit, continue till the jar is full of fruit to the bottom of the threaded collar, pour boiling water in to leave half an inch of headspace, then the jars go into the canner for the appropriate processing time. They always turn out just fine, I believe my "cheater" canning "syrup" is considered a "light syrup". I do the same with pears.