Studies on that are inconclusive at best, mainly due to the fact that people who rely on caffeine for daily function often do so due to having issues with sleep in them first place.
And no it’s quite likely not the the chicken the the egg problem.
Don’t get me wrong downing 3 double espresso shots 30 min before bed time is probably not a good idea however there is nothing that indicates that caffeine consumption during the day would have an impact on sleep in fact many studies showed that moderate amounts of caffeine even 2 hours before bed did not have a negative impact on sleep and a few studies even showed improvement in REM sleep when caffeine was taken but again nutrition studies are notoriously problematic.
I drink coffee/espressos each day, probably too much. Just recently after not having my usual Americanos I had a massive headache before bed. Advil did nothing so I figured it must be a caffeine withdrawal headache. They're hell and there's no way I can sleep with one so I made a shot of espresso and downed it quickly. Within 30 mins my headache went from a jackhammer pounding my skull to a distant woodpecker, and after another 30 mins I was asleep and slept fine. The big confounding factor with caffeine studies might be tolerance.
I had a similar experience on a long flight. I figured I'd avoid caffeine so I could sleep better, but I just woke up a few hours into the flight with a bad headache. Headed back to the galley to get some coffee, then slept halfway well.
Excedrin or the generic OTC "migraine" medications are good for this: a bit of caffeine, aspirin, and acetaminophen. Easier to carry around than having to scout out coffee and a bit more general purpose than caffeine pills alone.
The big confounding factors with caffeine is that nutrition based studies are extremely hard to run to the point where they are almost as bad as sociology studies.
Controlling for all the factors is nearly impossible.
Age, life style, genetics and everything else in between introduces so many variables that you simply can’t estimate or predict their impact on the study.
Even in your specific example it might be caffeine dependency or it might be something else completely like giving up 3-4 americanos a day and not making up for the liquid intake loss which left you more dehydrated in the evening.
Long time ago when I was chronically tired and with random sleeping patterns (going out, staying late...) I could drink strong coffee 30mins before sleep and have no problem getting to sleep. But some time later when I normalized with daily rhythm and stress I could not, I had to drink last coffee before 4pm, then a few years later before 2pm and less coffee. Now, when I am religious about getting to sleep before 11pm and am mindful about my energy levels, stress, eat well for long periods, train moderately, one coffee in the morning is more than enough to feel strong kick until the evening almost. I am thinking of even dropping that for some black/green tea. I think that so many people are chronically overstressed, undersleeped and with overworked adrenal glands, that they can’t even notice the real downside until they get into a better position for some time. And coffee in a run down body is just for keeping things bearly going.
Anecdotally as a caffeine addict I sleep fine but worry a bit about the opposite problem, that after the morning coffee effect wears off I get sleepy. I'm not sure if I might have more consistent energy if I stopped.
The main one has to be worse sleep quality.