On the home page itself there is the log in button. Once you click on the log in button, a pop up will emerge where you will get the options to log in via email or via you google or social media accounts.
There is no need to navigate to anyother page, as you will get all the options to log in from the home page itself.
You will find the log in button on the top right corner button in the home page.
As for the google log in, the first time you registered your account, you mentioned that you used google log in button to register using you google account. That is why by default you can enter by using the google plus log in button.
It would not create any issues or delays to your login.
If you are not able to find the access the log in pop up then, please share the screenshot and we will verify it and rectify if required.
Keep us udated.
(In the meantime, I will verify with the technical team, if your default login access, you created while registering at DB can be changed)