My golden has a weird red patch on her belly - normal or vet trip?

So I noticed a red patchy area on Maple's belly this morning when I was scratching her. She's a 3 year old golden. No crustiness, doesn't seem to bother her when I touch it, but she's been licking at it a little more than usual over the past day or so.

She hasn't changed food, no new detergents or anything like that I can think of. She did spend a lot of time in the backyard yesterday though. Has anyone dealt with something like this before? Trying to figure out if this is a "wait and see" thing or if I need to get her in this week.