All of this is just my opinion and because I have ZERO experience hunting in the south this may be 100% useless. But being a self taught deer hunter in an area of low deer numbers....I see some comments in your post that remind me of my early days.
The power of KROW Knowledge, Reasoning, Observation & Wisdom with the 3P's practice, patience and persistence will serve you well in the deer woods.
Figuring out if the rut has started should be a simple matter of observation. Are you seeing rubs, scrapes or even signs of bucks chasing does in the area you hunt?
3 non-productive hunts isn't a reason to panic. It may be a reason to do some evaluating, but not panic. Cat's suggestion of a trail cam or two could help you with this.
Are you sure/have evidence of the deer being nocturnal? Again trail cam would be a big help.
What you spend on your hunting gear has nearly ZERO impact on the deer you will see.
First you need to see and confirm what is going on. Look for your rubs and scrape and spot light some areas at night if legal (leave the gun at home). Also confirm your nocturnal theory. Get a cheap cam or two and put them up or simply get down to bare soil around your bait pile and rake the surface loose. Check the soil every new hunt and re-rake to get an idea of if deer are visiting your pile or not. A lot of tracks many mean one deer stayed a long time, but different sized tracks will indicate at least multiple deer. Deer also seem attracted to bare dirt for some reason. You can do this on deer trails as well. When I started hunting....I hunted for 2 years with a gun before I took my first deer. Yes is can be frustrating. You simply have to turn that into persistence, but not just staying the course. Sometimes you have to realize when you need to make a change....deer patterns change. We have to change with them at times. Sometimes sign is only evidence of what happened...not what will happen again. You also may need to evaluate your hunting location as well. If the deer are pressured you will need to look for heavy cover areas to hunt near. Ending up empty handed is one thing....not learning from the experience is totally different. I didn't learn to ride a bike in 3 tries....I doubt you did either. It takes time to gather the knowledge and to apply it. Don't panic....try to adapt to the info you have and the new info you may gain.