Hi and welcome,
Uncles, Aunts, cousins or grandparents, dx with MS are less likely to have any bearing on your situation, there are only a slightly higher odds when it's a parent or sibling dx-ed, the further removed you are genetically from the dx person the lower the odds again. It's actually more common to be the only person dx in a family, MS is not known to be an inheritable condition, MS can run in families but it's not common like many of the other autoimmune conditions are.
Q: I also have sleep issues, IBS and severe sinusitis, can any of these cause the first symptoms I mentioned at first?
A: IF you have something like a structural spinal issue eg degenerative disc disease, pinch nerve, arthritis, cervical spondylosis etc etc it could possibly account for the toe twitching, back and neck pain, and some spinal issues can also cause audio issues like tinnitus too but it's possible your severe sinusitis is the cause of your sleep issues, morning headache, eye pain as well the audio issue....
Nothing you've mentioned would typically be suggestive of a neurological condition like MS, i suggest you see your physician for a general check up and discuss the issues you're dealing with every day.
I hope that helps....JJ