I can really relate to what you wrote.. I'm also having to interact with lots of new people lately, and it's been wearing me down.
You're not alone! Having aches and pains are totally normal for people like us, but it is really hard to not feel good so often, and to have so much more stress than is healthy. Here are some things that I do, that help me:
-Distance yourself from others when possible. Maybe there's a more secluded place at the library that you can work, or a place besides the library that has better energies. From my experience, the atmosphere of public libraries usually lends itself to negative energy, especially in the computer areas Not sure why...
-Make sure your breathing is good. Breathe in positive energy (into your abdomen), and breathe out the negative energy (from your abdomen) *make sure your abdomen expands when you breathe, not your chest, and it will make a big difference
-Make positive changes in the other areas of your life that you can. It sounds like you have a LOT going on at once! Change in general really weighs on me, too. But I find that if I give myself the things that I need, in addition to my work and the other (hard) things that are necessary, I feel better and am more able to cope. Some examples are: time alone, time in nature, exercise, healthy food, enough sleep, and time to unwind before bed (I take at least an hour every night to do something that I want to do, whether that's watching a movie or replying to posts on here.. anything relaxing really helps)
*Oh and lastly, a note about sleep. It's my knowledge that for empaths especially, sleep is vital, because our nervous systems are way more sensitive than average and they take in a vast amount of information every day, so without at least 8 hours of sleep a night, we are not giving our bodies nearly enough time to recharge. I've found that some days I really need a nap, as well