What can I do if my allowed duration of stay in the US (based on the passport stamp) is too short? [duplicate]

Completely paranoid about my last experience with US Immigrafion.
Leaving the Bahamas(my home) I had a very interesting encounter with an immigration officer.
I approached the counter and was asked the usual questions, I was then asked when was the last time I was in the U.S. and I politely told the officer that I didn't remember the exact dates as it was over 6 months ago and that she had my passport so she can verify.
I guess that was suspicious to her since it escalated into a bigger ordeal.

Completely unaware of the severity of no phone policy as I've never had a difficult experience when traveling to the U.S. I attempted to call my mother to get the exact dates and the lady completely lost it and told me to put my phone away which I did.
She then took my passport and asked me to go into this small white room, obviously some sort of secondary questioning/screening.
I waited for almost 30 minutes until she finally arrived and told me "unless you want your visa denied you better have some answers".

I was in complete disbelief that she refused to look in my passport and see the dates.
She then asked me to approach the counter which I did and I apologized to her for not being able to remember the exact dates as I had literally just found out my dad has stage 4 cancer and my mind was clustered and that I'd never thought to memorize the dates as I know they are stamped in the passport and the officers usually verify themselves.
I then tried to remember the dates and I told her I was in Vegas from August until September and then she brought up the fact that I was in Charlotte and Houston to which I let her know they were simply layovers and I never left the airports.

I made an honest mistake of genuinely forgetting a weekend trip to Atlanta in November which she brought to my attention and I apologized for it. She then proceeds to thoroughly check my bags and upon finding nothing suspicious, takes my passport and returns it with a stamp that says I must return on or before April 29th, extremely puzzled I reminded her that my return flight was for May 5th and she said that means you need to change your ticket and be back by the date stamped in my passport.

I've always had my passport stamped with a maximum of 6 months admittance but this time it was stamped for a little under a month as my departure was April 8th.
I'm extremely worried about whether or not this will affect my future travels as my mom, niece and I have already planned to spend the entire summer with my sister in Vegas.

Will this experience affect my future travels and not being admitted for the usual 6 months?