I want to be physically intimate with my gf
Weren't you physically intimate with her before?
Yes, but now she's pregnant and I feel uncomfortable.
Showing affection for your partner is nice. Being selective about how you do so while being inconsiderate of their condition can make you seem inconsiderate. She may feel as if you see her differently and feel unattractive just because she's pregnant now.
Never cared about getting an unwelcomed child.
Whoever this unborn baby is from it is expected of you to take care of your girlfriend's baby once they are born and I do hope you get a paternity test to see if it is really yours or not. If it is yours, then I think it is right to take care of them until they become an adult, and if it is not yours then you can try to decide whether you want to still take care of them or break up with her.