Brief Answer:
if you're suspecting spider bite, please refer to your nearest ER at the earliest...

Detailed Answer:
Hello there,
Welcome to 'Ask A Doctor' service...
I've gone through your query in details...
I can understand your concerns...

Please note, spider bites contain numerous poisonous venoms based on the different geographic regions and different types of spiders. The only way to ascertain in by going to the nearest Urgent care/ER for a prompt check-up, management can be done based on the findings...

In case you've had any previous issue of a varicose vein or any disturbances related to blood circulation in the right leg, then DVT (Deep Venous Thrombosis) should also be ruled out after a prompt examination followed by Doppler scan of the veno-arterial system of the right leg.

However, since you're suspecting a spider bite, I would recommend cleaning the area with soap and water, calling for help and visit your nearest ER for a prompt check-up (after toxicological assay, they'll administer the anti-venom/antidotes accordingly)...You may also require a Tetanus shot additionally...

Meanwhile, don't move the right leg, apply some ice-compression, keep it a bit elevated, keep drinking plenty of water...If there's any itching, you may take an antiallergic (eg. Benadryl)...

Please don't panic, but please don't delay any longer and visit the nearest ER at the earliest...

Let me know if I can assist you further...

Take Care
Kind Regards

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