It is normal that they jump, especially when you touch their backs. I try to always touch the snout first, rub them under the chin, and let them pick up my scent (licking). Kind of what you are told to do with dogs. If I have to just pick up a gecko, I try to put my fingers under the belly and not touch the back first as well. Once my geckos are on my hand, they are all OK with me touching their backs or even their tail, but only after they know it is me. And sometimes they just have their moods (see my latest post in the chahoua forum).
It is also totally normal that a 3 gram gecko is very flighty. I would not do much handling at all until it is at least 5 g. That is what I ended up doing with my uber-flighty hatchling, and she turned into an amazingly outgoing adult.
For the first handling sessions I was very careful to 'gecko-proof' the room before I took her out. I stuffed towels in small spaces I did not want her to hide in, stuffed the gaps under doors, etc. Initially I even took her little tub inside a screen tent ('instant' popup tent, super easy and fun :-)) and only handled her in there.
I also 'practiced' with the wild lizards, green anoles and house geckos, around my house. A cool side effect is that I got better at 'catching' them without stressing them too much and grabbing them, which is great if you need to relocate one from inside the house (or even our lab...).
Good luck! And you are not a 'worrywart', just a responsible gecko owner!
1.1.0 Crested Geckos "Jackson Pollock" and "Pumpkin Spice" 1.0.0 Chahoua "Urmel" 1.1 Red eared sliders "Freddy Krueger" (25 years) and "Mucki" (45 years) RIP Peppermint (Green Anole)
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