Hello and welcome to OpenStreetMap!
You've extended https://www.openstreetmap.org/way/46343328 here up towards the north of Callendar.  Previously, e.g. at https://overpass-turbo.eu/s/2gqC , the national park boundary followed the river.  Now there's a duplicate line that you can see at https://www.openstreetmap.org/relation/1957067#map=12/56.2578/-4.1927 .  I'm guessing that your route west of Cambusmore Quarry is correct, but I've no idea of north of there.
When you've finished editing you can check it with the JOSM validator (see https://www.openstreetmap.org/user/SomeoneElse/diary/406398 for help with that).
Best Regards,
Andy
PS Any questions, please don't hesitate to ask!
