5 Month Old Hit Her Head

My 5 month old loves standing she hates sitting and I went to put her in her rocker and she bolted up trying to stand in her rocker and hit the back of her head on the hard plastic part and she cried for like 5 seconds and then started laughing, she's still giggling and talking alot , not crying , not rubbing her eyes , and very active , I just hope she's okay ... she's hit her head before but never the back of her head and she still has her soft spot.... it didn't change, it didn't get any deeper or swollen , she doesn't have a knot ...