Does this look like an insect bite?

[Charley557]

I have woken up with the bruise on my calf. No injury has caused it so seems random.
I have had itchy legs for a few days and was out in a park all today several days ago.
Would a bite cause such bruising?
FYI, I’ve never knowing been bitten before.

Should I be worried?

It looks from the photo as though there is more than one mark, so I'm wondering whether it might be a spider bite. They can cause bruising and (as I once had) cellulitis, so maybe show it to a pharmacist tomorrow.

Thanks for your reply. Are spider bites serious or do you just wait for it to heal by itself?