Hi there and
to the forums!
I'm sorry to hear that you were given such wrong information. Clipping the wings does not help with taming, it only makes them unable to get away from you when you approach if they are afraid, which actually leads to them being more fearful in the long run. The objective of taming and bonding is to gain their trust, not forcefully give them no other option. Also, they should have never told you to clip the wings yourself. It's very easy to hurt the bird like this.
I agree with FaeryBee, it's important to see how the feathers look. Obviously he's totally unbalanced and isn't able to move around normally as he's incapacitated by the loss of his feathers. He's probably even more scared now that you had to pick him up to trim his wings and it's probably not helping that you pick him up whenever he falls.
Budgies don't like to be petted or picked up and even if you little guy did, you should never touch him in the first few weeks of coming home as he needs time to adjust to his environment. If he's not fighting when you pick him up, he's probably being submissive because he's terrified
If he falls very hard and is unable to get around at all, put a soft towel at the bottom of the cage so that if he falls on it, he won't get injured, as FaeryBee said. Be sure that his nails can't get caught in the fibres; a smooth cloth with no frayed edges is best.
Meanwhile sure to acquaint yourself with the forums by looking through the links provided above, which include most of the many articles and stickies that we have here! If you have any questions after reading through everything, be sure to ask as we'd love to help. It's never too late to learn about the best practices for caring for budgies!
Keep us posted on how things go, we look forward to meeting him/her!