Car broke down on way to work this morning. Gearbox issue.

[Spoonaltap]

Yesterday is was difficult to get it into 5th gear, I needed to rev the engine a little to get it in without forcing it. This morn is was very difficult to get it into 5th when going to work which got worse and worse till the gear stick actually got stuck in the gear with no drive. I panicked so I pulled it out of gear with some force and now I can't select any gear. The lever is pointing in a forward position and can be pulled back but theres no way to get any drive. I can see down the back of the engine bay and the two linkages I can see are still attached.

I'm worried ive maybe knackered the selector shaft in the gearbox or something along those lines but I'm really hoping it's just the linkages that are knackered. Can anyone help?