Is my girlfriend too strong?

so i've been dating a girl for almost 10 days now.
but she is really really strong im a 140 pounds.
and my girlfriend lifts me up with 1 hand easly.
i also got a big box full of books and other stuff inside my room.
when she asked what was inside i told her she should look.
but i warned that its heavy because that box is like 200 pounds
she just took it off the closet and kept it in her hands.
and said: "its not heavy at all"with a big smile.
i wanna hear your opinion. is this even normal.
cuzz when i try to lift her its no deal. its just way to heavy.
but she's not fat at all she's skinny.
and well she does go to the gym 4 times a week.
but i think this is rather insane.

UPDATE:
i just sad on my bed and my girlfriend her phone fell under it.
when i wanted to stand up.
she just lifted the bed with 2 hands. kept it hanging with 1 hand. grabbed her phone. and sat down next to me. and i was on the bed the whole time!!!
Is my girlfriend too strong?
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