Does the jaw joint and square jaw Botox procedure take a long time?

Maybe it's because I have a bad habit of clenching my teeth while sleeping, but my jaw muscles have developed so much that my face is turning into a total square SpongeBob ㅠㅠ It's getting worse day by day... I've tried various things to reduce jaw muscle size, but everyone strongly recommends going to a dermatologist and getting Botox. Since I work, I'm planning to squeeze in a quick visit during my lunch break on a weekday. I'm curious how long the consultation with the doctor, ice pack application, and the actual Botox procedure itself take. If the pure injection time while lying on the bed is really short—around 5 minutes or less—I think I can get it done quickly without any hassle! I'm also wondering if there is any bruising or swelling afterward. Please leave a comment if you're a working professional who has been there!