Most B Complex 'stress' formulas are very low dose. I have not seen one that isn't. I recommend a B-50 or B-100 Complex plus B-12 and some B-6. Unless you took a bunch of B-Complex the same day, you did not overdose.

Although I agree with taking Vit C, a B-Complex with C is likely almost worthless in B dosages.

Feel free to post the brand or dosages of what you are taking. I can easily critique it.