Replies will be left here when people can help. Please tell more about your problem. What version of InDesign? What operating system?
if you refer to arrow head scaling using InDesign CC 2017 the range goes from 1% to 1000%.
Unfortunately the percentages do not follow a linear proportionality of the size we see with 100%.
My view: That's a big conceptual failure of the feature.
What you can do to get the size of the arrow head below that limit:
1. Multiply your stroke weight by 10 to 10 pt
2. Lower the percentage of the arrow head scaling until it fits your needs in proportion of the stroke
Beware of a different limit here: Scaling below 65 % could mess with the shape of your arrow head, because the stroke will overlap the arrow head. Another conceptual failure.
3. Go to Preferences > General and set the scaling preferences to Adjust Scaling Percentage
4. Scale the object to 10%
Here two screenshots from my German InDesign.
Note that I scaled the view to a maximum of 4,000 %
Depending of the kind of stroke and the kind of arrow head sooner or later you'll see, that the stroke will overlap the arrow head: