did you have the extraction done with local or general anaesthesia? which anaesthetic did they use specifically?
have you done nutritional testing in the last 18 months to rule out imbalances known to be associated with ms? these same imbalance could affect your energy level and risk of low grade infection.
i used to have pretty bad fatigue, plus susceptibility to colds and flus, not to mention a range of other seemingly minor and disconnected issues. I spent the last 7 years researching nutrition science and one by one correcting my nutrient imbalances and deficiencies (before dx, i had a whole food diet - no junk food, but extremely incomplete nutritionally)
at this point i have way more energy and rarely can a cold take me down. at worst I become aware that my system is fighting something, but life goes on business as usual.
also, a family friend had chronic EBV lasting a couple years. I have gone to visit twice, to set up nutrient testing and a therapeutic regimen. finally got the good news that the tests for infection were coming back negative. intermittent food sensitivity test results improved dramatically in the same time period. at this stage when I hear complaints of lymph node swelling it's inevitable that the food combinations and supplement choices will be significant contributors. at any rate, there is a known association btw EBV infection and MS. as far as i'm concerned it means you have to bolster up a weakened immune system (which may sound odd re ms, but in the case of auto-immunity you need to strengthen the immune system's 'brakes' signaling)
hope that helps
more reading, if interested: