Worried about the outcome of my FUE transplant - blank spots the day after. (photos)

If there are blank spots then the blanks spots will not have hair.  This is a logical conclusion.   How that may impact your overall results is not clear until your hairs grow out. At this point, you can't do anything about it.  If you are concerned discuss your options with your doctor.

Really all you can do at this point is trust your doctor and wait for it to grow out. In 10 months if it's significantly patchy your doctor should hopefully offer to fix it for you, or if the results are fine but you just want thicker coverage that can also be done with a second procedure. Your picture looks pretty normal to me.

The most important two things in FUE is, how the donor area was managed and the growth rate of the transplanted grafts. This is determined by the quality of the procedure and some luck. If your donor area was used professionally, which means minimum damage and the lowest transection rate then perfect. If all the transplanted hairs grow that is excellent. Whether or not there remains some areas with less density will be a minor concern that can always be fixed.

the transplanted hair has a scab of dried blood around it, your native hair as long as it was not damaged during the procedure does not. This is likely the cause of why you see "space" because there is actually a terminal hair present. As long as you didn't have any active bleeding in that area post op, the chance of losing a graft is slim. Be patient. Give your results time to grow in, over the next 6-12 months.

Blank spots are dried blood crusts , no problem .you would wash your transplantation area gently in order to remove all crusts at operation field. Cleaning off the scabs on  transplant area takes about 10-15 days approximately. 

This is a normal post op stage . Transplanted hairs start to visibly regrow between months 4-6. At month 6-9, a patient may expect to see growth for  80% of the transplants. Again, due to the random cycle of hair growth, not all grafts will start growing at the same time. Initially, the hair my be thinner and finer. It will gain length and density as it matures. Full growth from the transplants is usually achieved at 12 months. In some cases, this can take up to 18 months. This is especially common in female patients. The transplanted hairs will continue to gain length over time.

You are worried about blank spots after FUE. but from the photos you supplied, everything looks good. Just wait it out.