I didn't have enough time to write a text yesterday, so today's text will cover Saturday, as well asnd Sunday.

Alternatively, you could write "a post" instead of "text." Also, I replaced "as well as" with "and" for simplicity's sake.

On Saturday, I had to wake up early for a ninepin-bowling tournament.

Me and my team met at the local train station, to take the next train to our destination.

As we arrived, we already saw another team and instantly knew, that it would be a tough day.

I only reachieved 434 points (my goal was at least 470).

Either "achieved" or "reached" could work for this sentence, I think.

Thankfully, the enemyopponent right next to me, had the same struggles as me and only scored 399 points.

I think "enemy" is mainly saved for wars and other violent fights. In all other competitive scenarios, I'd use "opponent" instead.

After I was finished, I tried coaching my teammates, wicho also had a lot of problems.

In the end, my (extremely bad) score, turned out to be the best one ofin our team (that's why we finished last place).

This was one of the most deviastating experiences iI've ever had.

When this event was over, I had to hurry, because I instantly had to go to a music gig for a 50th birthday.

I deleted "instantly" because I figured you had that nuance in "hurry" already.

There, I played some music with my band, and had a pleaseant evening, even though, I had forgotten my jacket at home, and it was somewhat cold outside.

However, I got to listen to my favourite local band and goet food for free.

Today was a less stressfull day, but I overslept an online instrument lesson.

This was less of a problem, because my teacher is real chill about it, and we just did it 30 minutes later.

Besides the lesson, there was only some work for school to do and some spare time I spendt with video games.

I think this was a really nice and productive weekend, so I am verry happy.

I didn't have enough time to writmake a texpost yesterday, so today's texpost will cover Saturday, as well as Sunday.

"Write a text" sounds unnatural so I changed it to "make a post" since that fits the context of the platform better.

On Saturday, I had to wake up early for a nine-pin- bowling tournament.

Me and my team met at the local train station, to take the next train to our destination.

"To our destination" isn't needed since it's implied

As we arrived, we already saw another team and instantly knew, that it would be a tough day.

The bowling alley was somewhat crappy and it held me back, but my performance was the worst in the last 2 years.

I only achievedgot 434 points (my goal was at least 470).

"achieved" is for when you win something or complete a goal

Thankfully, the enemy player right next to me, had the same struggles as me and only scored 399 points.

After I was finished, I tried coaching my teammates, wicho also had a lot of problems.

I changed it to "who" because I think that fits what you're trying to say more. "Which" implies that you had problems coaching them while "who" implies that they were the ones having problems.

In the end, my (extremely bad) score, turned out to be the best one of our team (that's why we finished last place).

This was one of the most deviastating experiences iI've ever had.

When thise event was over, I had to hurry, because I instantmmediately had to run to a music gig for asomeone's 50th birthday.

I'm assuming the 50th birthday is not your own so I said "someone's"

There I played some music with my band, and had a pleaseant evening, even though, I had forgotten my jacket at home, and it was somewhat cold outside.

Today was a less stressfull day, but I overslept an online instrumentmusic lesson.

This was less of a problem, because my teacher iwas really chill about it and we just did it 30 minutes later.

Besides the lesson, there was only some work for school to do and some spare time I spend witht playing videogames.

I think this was a really nice and productive weekend, so I am verry happy.