Hi and welcome,
It's highly likely what your experiencing is associated with being anemic and nothing more serious......in regards to MS there's nothing suggestive/consistent with these types of symptoms you've mentioned to put MS high up on the potential causation list. MS is not really a genetically inheritable condition, there are slightly higher odds of being diagnosed with MS when there is a first person relationship ie parent or sibling but the odds decrease with each removal but there's also environmental factors to complicate things further.
It's actually not uncommon to be the only MSer in the family but if say you had your grandmothers sister (great aunt) diagnosed with MS on one side and a first or second cousin on the other side, your odds of also being dx with MS would basically be the same as anyone with out any family relations. sorry not sure that isn't more confusing than helpful.....basically if the people in your family who are diagnosed with MS are not your parents or siblings, you wouldn't have the typical genetic connection/susceptibility for MS to be of a higher probability than the general populous.
Information:
http://www.eyeonvision.org/visual-snow.html
"Visual snow (VS) is the persisting visual symptom of seeing snow or television-like static across their visual field. The snow and static tends to be worse in the dark, but can be seen in all lighting conditions.
VS should not be confused with normal entoptic phenomena or vitreous floaters. While these two conditions also cause you to see spots and floating objects, this is not the same as VS.
There is no known cause for visual snow. Through documented case studies illegal and legal drug usage can sometimes lead to VS, but little is known on the specific causes. A few connections between HPPD, auto-immune disease, and lyme disease have been found. However, far more cases of visual snow have no connection at all to another condition.
Although the vision is affected, very few people have had irregular eye test results. Most come back within normal range, leading doctors to believe that patients may be making their symptoms up. CT scans and MRIs also tend to come back normal, again stumping doctors. It is more likely to be an undetectable chemical imbalance in the brain.
The term visual snow is rather limiting for the condition as there are numerous symptoms that patients experience above and beyond visual snow. Many people also see after images, vitreous floaters, entopic phenomenon, glare, halos, starbursts, trails, palinopsia, double vision, odd colors and shapes. Many sufferers also have non-visual symptoms such as fatigue, tinnitus or depersonalization and derealisation."
IF you've always had visual snow and your recent visual testing was normal, it might be a situation where your life long visual issues worsen when your unwell, which would add to your fatigue, concentration difficulties, headaches, feeling heavy headed, nodding etc
Obviously only a dr can diagnose, from my lay persons perspective and understanding you have recently been diagnosed with anemia and that's likely still an issue despite the iron supplements, and definitely worth seeing your family dr about again.
Hope that helps......JJ