Question

What’s the difference between:

 sh myscript.sh

and

./myscript.sh

Answer 1

#!/bin/sh loads sh from that path. If on Linux then it is likely a symbolic link to bash.

sh tremor_script.sh uses the PATH environment variable to find sh, which might be totally different.

Track down which sh you are using, maybe using which sh, and following any links.
Note that Android uses ash or mksh, depending on the Android version.

However, messages like “junk at end of line” might come from files that have been copied from Windows without the \r\n line endings corrected to \n.