Someone please help diagnose my sick ? begonias

Can anyone please help me identify the issues with these two begonias (pink spot, and Inca flame). These are both 2 weeks newly acquired from different locations. The pink spot has pinkish tan streaking appearing on some of the leaves. I did not water it since I got it because of how well the soil was holding water. I let it dry on top then replaced the soil with my own mix with better aeration to keep it from holding so much moisture. I did water it after the substrate replacement 2 days ago. I also have noticed some black spots on 2 leaves. I think I’ll just remove those but I’ll include it as well. The streaks are neither wet and wiggly not dry and crispy. Somewhere between. They seem thinner than the healthy parts, but feel very similar. It’s hard to tell because the leaves are so small and the patches are small for my fingertips to really get a good read.

The Inca flame has… issues… coming from Lowe’s, but what is concerning me most is this black-ness along some of the leaves veins. I’ve seen it in some examples I’ve found online and not seen it in others. I don’t have a clue what it is. (This one had soil changed out as well).

Both have been looked over for pests and I’ve seen none. I had my husband check as well. However I can’t find my jewelers loupe so I didn’t get the closest look at everything. Just with our naked eyes.