Those marks on the leaves are not spider mite caused or signs of spider mites., they can be caused by water on the leaves and sometimes also be just normal "blemishes".........no plant will ever have 100% perfect leaves, 100% of the time.
Spider mite damage generally looks like tiny yellow/white dots everywhere the mites have sucked the sap out of the leaf.
The little black dots are not spider mites either, mites will scoot around and leave webs behind.
The dots are hard to identify in the pictures...........if there are only one or two, just squash them.
No need to poison your baby plant with sprays because you imagine there is some sort of major plague attack going to happen.