GPG issues with sending and receiving keys

I’ve experimented a lot with GPG the last couple days and one issue persists:

Someone signed my GPG key and published it to a keyserver X. I can see on the webpage that his signature is shown under my key, so that worked. But my local PGP doesn’t understand:

gpg --keyserver [X] —refresh-keys [myKey] gpg: refreshing 1 key from [X] gpg: key [myKey]: [...] not changed gpg: Total number processed: 1 gpg:              unchanged: 1 

If I check my signatures, that new signature doesn’t appear.

gpg --list-sigs [myKey] => only outputs the signatures I already had before (either manually imported or signed by other keys that belong to me) 

Also, when signing a key and performing a --send-keys, it throws no errors but the key just never arrives on the servers. This only happens with some keyservers. I read something about ports maybe being closed by the firewall, but didn’t find any concise answer for what to check and how to fix.

Thanks in advance!

PS: Sometimes, the webinterfaces of the keyservers I’m using just load forever or are generally very slow or unreachable, is this normal?