Are these numbers considered high platelet count? 384. it was flagged as high on my lab reports as their range is 150-379. all other results normal

Probably not bad: Normal lab ranges are based on averages from healthy subjects, so there is always the possibility that a value slightly higher or lower than normal is perfectly fine. Sometimes elevated platelets are due to a passing viral infection or other self-limiting condition. If you are otherwise healthy it's probably ok not to worry at all, though you could repeat the test in 4 weeks or so, if concerned.

It is high: it is high somewhat but only few points. Usually the lab values have a range value of normal, so this may not be really high.