Hello mam, thanks for trusting health care magic.
there is nothing to be embarrased about girl and rather im happy seeing your concern at this age.
in early years of menstruation
a little irregularity is normal so just wait for natural periods to come and if still they dont then get a pelvic ultrasonography
done and visit your gynecologist.
In case you have further questions you can consult me on health care magic forum and i will be happy to help
Take care and wish you all the best.
Dr Manisha Jain.