I agree with posters above: on a purely domestic trip there is nothing special to be concerned about. Plenty of business travelers do same-day returns. It will not raise eyebrows.

The only time an airline or airport employee has even noticed my same-day return was on an MR at an outstation when I boarded the same aircraft with the same crew that I stepped off of less than 30 minutes earlier. The FA expressed concern that I may have gotten on the wrong plane; she thought that perhaps I had read the wrong BP when making a connection. I said, "Nope, I just like flying," with a wink and sat in the same seat I'd arrived in.