I might just have had a major screw up.
I created a bitcoin wallet with Electrum (bip32 standard). I then used the xpub key (extended public key) to generate payment addresses in my online store. It looks like my online store plug in uses the bip44 standard. This resulted in different "receiving address" then the ones generated by the Electrum wallet. Unfortunately I didn't notice until I received the first BTC transaction.
I tried to enter the seedwords from my Electrum wallet in the Mycelium wallet which I believe is using the bib44 standard. I got an error message that the checksum of the seed doesn't match.
BTW, the addresses generated by Electrum start with "1", the addresses generated by the webstore with "3".
Am I screwed?