This small amount of sun exposure isn’t likely to affect your results.
From your description, it doesn’t sound like the quality of your results should be affected by this brief sun exposure, although it is important that you try to keep your skin covered or use broad-spectrum sunscreen to prevent future damage. If you begin to notice any adverse side effects, contact your medical spa for a more detailed assessment. However, I think you should be fine from your short walk to work today. Best of luck to you!
How damaging is brief sun exposure after laser hair removal?
Based on the details of your question, it doesn't sound like you should be too concerned. There are other variables to consider though. It is ideal to avoid extended sun exposure after having any treatment to the skin with an energy based device. However, in real life, that's not always possible. Next time, an SPF of 15 or 30 on the exposed/treated areas should give you the protection you need.
If you don't see or feel any negative effects from the brief sun exposure, you should be ok. It is always best to avoid excessive sun 2-4 weeks before and after laser hair removal. Keep an open line of communication with the practitioner to stay safe and maximize your results.
Always make sure that you are treated by a professional with the right credentials to do laser hair removal, based on the laws of your state.
Have a great day!