The phrase "after I first started" is correct and usable in written English.
It can be used to refer to a time period following the initial beginning of an action or activity.
Example: "After I first started learning Spanish, I noticed a significant improvement in my communication skills."
Alternatives: "once I began" or "following my initial start".
Some years ago, not long after I first started working as a TV producer, someone sitting next to me at a wedding asked me what I did for a living.
But now, some five or six years after I first started using the term singlism in my book, Singled Out: How Singles Are Stereotyped, Stigmatized, and Ignored, and Still Live Happily Ever After, and in my early writings with Wendy Morris, I have much more than a litany of anecdotes and complaints to go on.
A federal judge's recent ruling has finally settled outstanding issues in the black farmers' long-running lawsuit, nearly 30 years after I first started protesting discrimination by the United States Department of Agriculture, Congress and the Department of Justice U.S. District Court Judge Paul Friedman's recent ruling will put to rest the expectation of compensation that many farmers still hold.
Shortly after I first started smoking pot my freshman year of high school, I moved away to another town, and my access to pot was right back to square one, so I ended up hanging out and playing music with a group of dudes whose views on pot were unclear.
Definitely after my first one when I first started, I was like, Wow, what's going on?
Definitely after my first one when I first started, I was like, 'Wow, what's going on?' Like I did feel a high".
I first started working after I finished my master's degree.
"When I first started auditioning after college, I had some pretty lean years," she wrote, and continued: "I remember entering an Oscar pool with the other waitstaff at the restaurant I worked in.
Ali said, "One evening not long ago — this was after I came to America — when I first started to go out with Sweeny... Have I told you about Sweeny?" "No".
"Art is like the reverse of a trigger," says Bell. "I thought it was a load of arse when I first started, but after trying it and learning a little about why it works, I've had my eyes well and truly wiped.
YEARS after I first returned from Iraq and started having thoughts and visions of killing myself, I'd call the Department of Veterans Affairs.
