Chrissy & Penny <3

Guinea pigs are prey animals, and they're naturally skiddish. When something big like us is hoovering over their cage, their first instinct is to run and hide. Don't take it personally! A few things you can do is to associate yourself with food. You guinea pig should be getting about a cup of veggies a day containing romaine lettuce, 1/8th green pepper, cilantro, and whatever else you have for the day. Everytime you go into your room or have your piggie in your lap give her/him something to eat! Eventually he/she should take food from your hand. Overtime you guinea pig will learn to get excited when you come into the room.

Bonding with your Guinea Pig! - YouTube

One of my guys has been like that since we brought him home(about 7months ago). He loves lap time but when he's in his cage he wants nothing to do with me! He will take food from my hand but scoot out of touching range.

Welcome and don't feel so bad.
Piggies take time depending on the pig as to how fast they get used to being handle.
They have a mind of their own... :melodrama

I'm sure she will come around soon.

My newly adopted piggie: Princess Penelope or Penny as my wife calls her "BUT" she thinks she is a Princess still likes to run from me by running around her cage several times until she decides to humor me and let me pick her up and cuddle for awhile.
But she's getting better every time I do pick her up and I've only had her for four days.
It just takes time, just don't push yourself on her feel her out as to what she wants and I'm sure she'll come around soon.