I lost control of my Space Station I think?

[Reposter]

Hi guys, I am still relatively new to the game and I tried building a Space Station just to experiment around with some of the building Missions I managed to get.

What happened was I was experimenting building a Space Station to have 5 turrets and I think 30000 Container space. I only had 3 Million Credits, so I just put a few base modules together and it cost more than 3 Million Credits. Then I am not sure what I did, maybe I clicked confirm building, and I could not re-enter the building screen.

I tried reclicking change modules but nothing happened? I think I screwed up something, could someone Please tell me how to avoid screwing up Building of A Space Station, and how to do it properly. I saw some YouTube videos but it did not explain why I could not re-enter the building schematics screen...

Just noob asking for enlightenment, please help if you can, thanks.