Linking devices issue.

First off, let me state I'm sure the problem is me being an idiot with tech, and nothing to do with my devices but here is the problem...

I have three devices at the moment.

Device #1 - Android tablet which has my main account I've been playing for 29 months.
Device #2 - Ipad I borrowed from family member to play my second account on as my old second device crapped out.
Device #3 - Android tablet I just purchased today and am looking to get my second account onto to give my family member their ipad back.

I just set up the new tablet and installed CoC. It gave me the option to choose an existing account so I typed in the information for my 2nd account... but it wants to load my main account?! Surely I could not have the same email and password running both of my accounts?

I try to link the ipad to the new device but it is saying that it can only link once and so I am unable to do so again.

I know the info for my second account is correct so I'm very curious why it is choosing to put my main account up instead. Was it somehow possible that I have two accounts running under the same gmail G+ account? If so do you have any advice on how I can sort this out as all I want in one account on one device, and one on the other but I've tried for over an hour with no luck and it is just getting frustrating.

It doesn't help that I am a lv4 noob at this sort of thing.

I did have an answer but then just realised something wrong in what you said... You said you are inputting your second account details on your new device, However, your second account would be a Game Center account as its on an iPad, so there's no way you could log in with those details on your new Android device.... So I'm confused

My (families) ipad device is hooked up to a gmail email and password. That is the game center information. Why is there no way this is possible? I assure you that it is happening now lol

I understand now. However, you are confusing where your bases are linked to. Even though your login on the iPad is a gmail account, it is actually the Game Center account (apples game save data facility) that you are logging into. On android devices, game save data like this is done via the Google Plus facility. I think I can explain what is happening but rather than post your logins here for all to see, if you PM me the login emails you say you are using now for the first two devices and what you are trying to use for the third, I can clarify this and tell you where you went wrong.