How often can I use vitamin c serum and retinol in conjunction with glycolic acid peel (used weekly)?

Thanks for your question. The combination of any of those products and the length of time your skin was exposed all play a role in the amount of inflammation and reaction your skin experienced. I would recommend stopping all of it until your face is not red and puffy, and when you do re-introduce products, just do one at a time and make sure you are tolerating it before adding something else. You should see a certified aesthetician that works under the supervision of a board certified dermatologist for a good long term treatment plan to address your concerns. You wouldn't want to end up with scarring or problems that you developed from too much product mixing and matching. Best of luck!