Am i selling myself short?

So i recently got a new job at a gas station. In Texas, minimum wage is $7.25 but because cost of living went up a lot of stores that used to offer minimum wage, are starting to raise their starting pay to $9 or $10 and hour.

So the interview went well but the manager said i would start at $8.75. i asked him what starting pay was and he said $8.25. i agreed because i didn't really know how to approach this but now I'm starting to think maybe I'm selling myself short.

For example, my mom just recently got a job at Whataburger and where I'm from, they're known for hiring teens because they start at minimum wage (again, this is where I'm from, another city in Texas might do things differently). Anyways so she recently got hired and they started her off at $9. Which i was surprised honestly.

Also, the placed i used to work at a year ago (fast food restaurant) payed minimum wage and recently they changed starting pay to $10!

Now, today in my interview, my manager mentioned how this particular gas station is taking over the other gas stations in the city. And it's true, where there was gas stations like Valero and 7/11, this gas station has taken over all of them.

So I'm wondering if they're doing so well why not ask for a higher pay? The manager said that after 90 days, i would get a 50 cent raise, which would then put me at $9.25.

I was thinking also, when the time is right, to ask my other coworkers how much their pay was. But i still feel like regardless, i might be selling myself short.

But at the same time I'm new, and i know i have to work for it but with the cost of living going up, and seeing all these companies raise their starting pay from minimum wage to a reasonable amount, it makes me wonder.

So am I wrong? What do y'all think?

Also please don't be an asshole, i had an issue in my previous job with something similar so understand i am not trying to get played again.