When l try to shift to 1st say im goin 10mph it always ''kicks'' back! l have to come almost to a complete stop be4 it lets me downshift to 1st... Is that how its supposed to be or what? Brand new clutch put in 2 days ago!
Top speed for 1st is 38mph

Worn synchroniser on first gear. Use second for ten mph stuff, it has the torque.

It is not your syncro. Your first gear has moved on the shaft ever so slightly. It is usually caused by downshifting too hard. You will need to take it to a tranny shop and have them replace the gear and shaft. Once it has been compromised, it will keep slipping. l have seen this 7 times on these cars. They are driven too hard.

The early WRX transmission did not really like to be downshifted into first all that much. There is most likely nothing wrong with it, however, you should never force it into first.

Welcome to the world of the 5mt. uggh