Clarification. Specific instructions?

Hello Doctor, I would like your guidance. Today was my first day at a new company. About two hours before reaching the company, I took 20 mg of Inderal by splitting a 40 mg tablet. I have social anxiety and performance anxiety. Usually, when I have to talk to female colleagues or seniors, my heart beats very fast and I struggle to speak. Today, I still felt a little nervous when I met a female colleague, but my heart did not race, and I was able to speak calmly instead of talking very fast. I also felt much less afraid while talking to my seniors. This made me feel much more confident. Based on this experience, I realized that if my anxiety is controlled, I can perform much better. Does this mean Inderal is helping with my performance anxiety? Is it safe or appropriate to use Inderal 20 mg before important work situations, or should it only be taken under a doctor's specific instructions? I cannot afford a paid consultation at the moment, so I would be very grateful for your guidance.