Phal abit wobbly in pot after repotting

[Asher]

Hi guys my aunt gave me her old phal at the weekend as she is having no luck with it at all. I decided to repot it today as she said it hadnt been done in years (very very bad) when i took it out of the pot it had healthy roots nearer the top of the plant which were quite short but very thick, most of the longer roots were rotted so i had to take them off. Now that it is repotted i've noticed that although the pot doesnt fall off when i pick it up by the leaves it is still quite wobbly at the top because of the shorter roots.

Is this a major problem should i worry and try again ? Thanks guys