Brief Answer: You probably over did it. Detailed Answer: Hi and thank you so much for this query. I am so sorry to hear about this bruise. I think you over did it because you did not realise any symptoms prior to stretching. If it were a bite or something that was there before, you would have felt some discomfort, pain , itches, etc. I will advice that you simply keep it clean and it should heal all by itself. It it should not improve within a week or get worse, then please get an appointment for evaluation. If possible, you may want to upload a picture for a closer appreciation and advice. I hope you find this helpful and it addresses your query fully. Thank you so much for using our services and feel free to ask for more information and clarifications if need be. I wish you the best of health. Dr. Ditah, MD

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