Bella - a warm welcome to the site.

There does come a point when we become 'tired of swimming' but we must keep trying anyway or we will sink. Stay strong and keep writing,

Ben

Bella, this is an honest write and most probably relatable to many of us here.

Title - it makes you may to read on about why there are mixed emotions and links to the content nicely.

The day you left me I will never forget.
^
Makes me question how long ago did they leave, why won't you forget etc.. Has a lover left or is it about a person you felt deadly about passing on?

I felt like I was in an ocean full of mixed emotions and feelingsand I was just swimming through
^
Wow, these is only one way being in an ocean is going to go for me is me drowning as I am scared of water because of the past so I never learnt to swim lol anyway being in an ocean with your own emotions is a fab image and makes me think of a person in water with all the Emojis surrounding them.
Separate feelings and, also I think the second and could be replaced with a comma though only a suggestion.

And I am tired of swimming. I'm done.
^
A powerful ending that states (of course) that you're done trying to swim through life. I think, and it's only a suggestion, that the 'I'm done' could be separated from the rest of the piece so the reader has time to digest it all.

Great first write posted by you.
Em