I'm concerned about my girlfriend's weight.

[Lotsgoingon]

You are allowed as a bf to ask how someone's medical tests went when that person tells you ahead of time that they're going for tests.

Yes, partners want to track the wellbeing of the other. It's a way of caring. You just want to maintain your frame that you are not criticizing her, you are only a little worried about her because you like her so much and you want the best for her. Always keep that tone and attitude.  And you can ask what you want. 

Anytime a partner shares some piece of information, that usually means it's fair game to ask about that information later. Not all that different than her telling you she isn't feeling well and you calling to ask how she's doing. Nothing intrusive there.

 

[ironpony]

Okay thanks.  I can keep it at then, if that's best.