Hi and welcome,
I really don't think you've mentioned anything from my understanding, that would be suggestive of a neurological condition like MS. Whilst Meralgia Paresthetica is nerve related, it is a nerve compression response, peripheral neuropathy (pinched nerve) of the Lateral Femoral Nerve, which is basically not the same as what happen's in MS.
Your don't mention there being abnormal clinical signs from your neurological tests and if your neuro has determined your foot numbness, is the nerve compression response from sitting, which also happen's even without crossing your legs. It probably means you didn't have any clinically abnormal test results (including any other test results you may have had eg MRI etc) to otherwise explain it, because If it had of been more than a temporary compression response, there would of been some evidence of this specific muscular weakness or paralysis.
Costochondritis can take weeks and weeks to get over, it's fairly common condition that is associated with some chronic medical conditions eg rheumatoid but it's more often a stand alone diagnosis. Costochondritis is inflammation of the cartilage where ribs attach to the breastbone (sternum) and this is a different issue to what you've possibly read about in MS.
In MS a similar issue commonly known as the MS Hug, when located in the ribs is due to the intercostal muscles (muscles between each rib) spasming and basically not allowing the ribcage to expand and contract correctly. This causes a tight constricting or banding feeling that partially or fully surrounds the torso and it is associated with spinal cord lesions.
Unary issues are extremely common in women because of the physiology of out bodies, hormones, being sexually active, pregnancy, type of underwear, weight etc etc increases the likelihood of unary track infections (UTI) during a women's life time. Urge issues off the top of my head are commonly due to pelvic floor strength, UTI's and even behavioural habits but if you are experiencing UTI symptoms i would suggest seeing your doctor about it as you may require antibiotics.
I honestly think these are non MS issues......is it possible because of the similarities of the issues you've mentioned and googling, you've come across similar MS related issues and may have inadvertently become worried about MS?
IF so, please try to not worry to much that these issues have to mean they are more than what they are, most symptoms you look up online will bring up MS, simply because there are many medical conditions with similar or the same symptoms as those associated with MS but it is not MS....
Cheers........JJ