Brief Answer:
Follow the Advises..

Detailed Answer:
Hello XXXX, Welcome to HCM,
I've gone through your query and understand your concern,

Good that you've already washed the area soap and water, however I'd suggest you to wash it once again thoroughly under forceful running water with soap..

Don't keep the area covered, keep it open air only..

Now, since it's a stray dog, first of all, try to keep an eye on the dog for next 7-10 days (if possible), try to obtain any further information regarding similar types of dog-bite in that area (because if it's a Rabies dog, there can be several similar incidents, and within a week to ~10 days, there should be a reported mortality of the dog)..

As of now, since there's no blood came out as per your descriptions and it's just a superficial bruise, nothing else should be done other than being vigilant about it.. But if you notice any woozing of blood or any deep wound/ excessive pain/redness over the area/ any fever, then it should be examined without any further delay and you may require a short course of antibiotics (eg. Co-Amoxyclav for 10 days) along with Complete Post Exposure Prophylaxis for Rabies..

If you've taken tetanus toxoid in the past 3 months, then fine , otherwise please get I.M shot of it too..

Don't worry, just follow the instructions as I've mentioned, and if you notice any of those symptoms, please visit your nearest Hospital/ER/Infectious Disease Dept for a detailed examination of the area and necessary management as per the findings..

Let me know how you stay in the due course..

Take Care
Kind Regards

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