The drug depletes the chemical responsible to control anxiety, depression, mood disorders in general etc.
So until these levels come back to normal (won't be long if it was a once off dose of 250mg, hlle even 1g you will recover from, itll just take longer you will feel flat and might want to supplement with something.
Phenibut is a great legal compound, works on GABA like valium etc so it relieves anxiety and give you a mild buzz. Wou'ld recommend some of this, helps you sleep really well also. Only use it sparingly (1/2 tea spooon 2x a day max) , one it does away you can save it for other generalised anxiety issues.
Personally I've found it better than benzos for anxiety due to the facct it can;t easily get you high, also its OTC.
Also get as much fresh fruit/vegetables, eggs, tuna and generic multi Vs as you can, a good diet is key to recovery.
I have no doubt you will be fine, you just need some time and to be healthy for a while. I'd still go see the doctor anyway, most don't care if you are asking about drugs because it seems you are looking for help.
Good luck