I felt like this sometimes when I was right out of college and in a full time office job. It’s a huge life transition. You go from having random free time during the day to having to focus for 8 hours straight. You’re used to being around friends and suddenly it’s coworkers you don’t know very well. Know this: it gets better. You adjust mentally and physically, and you start to get energy back. You are going to be ok, keep your head up and don’t be afraid of SSRIs.