Pulled loose a dissolvable stitch tonight only 21/2 days post Mohs surgery on my face. Will this affect the wound closure scar?

Yes there are options and I would consult with a plastic surgeon / dermatologist  and a radiation oncologist about the pros and cons of the different options. The problem always in making the decision is that there is no way of knowing how large the defect will be following surgical excision.

I would ask the advice of your PS. Generally if the wound has healed then one can start doing what one normally does. A chlorinated pool however may not be in your best interest and you should ask your PS.

This is a normal appearance at this stage and is secondary to contraction along the edges and edema - both expected at this period. With time this will diminish. Occasionally laser and/or steroid injections may be helpful.