Can't supercruise away from stars/planets

Sorry, I'm a newbie, and I cannot find answers here or on YouTube.

I'm trying to get to a station that's behind a star. I assigned Supercruise to a hotkey, then tried executing it while facing away from the star. I'm stuck at the slowest supercruise - 30k/s, not even making a dent in the distance from the star. I'm almost out of fuel. I'm extremely frustrated and ready to give up after researching and reading for a half hour.

No idea what to do.