SUBREDDIT: r/relationships
TITLE: Me [20 M] with my girlfriend [19F] of a year and a half
POST: So guys tell me if I'm overreacting. I haven't seen my girlfriend in almost 3 weeks. This is over our winter break and she went to a week long family reunion in south carolina in the middle of it. 

 She came back early and I asked if I could go visit her. She only lives 3 hours away.  She's supposed to come to my house in 4 days, but I missed her and figured she'd be excited to see me.  Instead she said she wanted to stay home alone because she's getting along with her brother and mom at the same time which never happens. She said she wanted "to stay home, watch tv, and pretend like it's high school" again. Am I wrong to be upset/skeptical about the relationship?
TL;DR: 
haven't seen gf in 3 weeks over break. She will visit me in 4 days but I offered to visit her early, gf declined so she can be alone. Should I be worried?