How did you know that your LO had reflux issues? What was it that made you look into it or convince you of it?

If you have a minute or ten to read this, I could use any and all insight:

My LO is a week shy from 6 months. She's had sleeping and eating issues since day one and I've attributed most of that to having a low supply (I EBF not by choice, but because LO refuses formula - we used to combo-feed until she weaned herself off of the formula) and to her being sensitive, I guess.

She cries on the boob and often seems upset or frustrated. This usually happens within 3 seconds to 3 minutes of feeding. I then switch boobs and she seems happy for a second, then gets upset. I switch back. Repeat repeat repeat. This is our normal feeding behaviour. If I hand express or pump at this time, barely anything more than a drop or two comes out - hence my feeling that it's low supply. But she's overall a good weight and is gaining, so she must be getting something.

As for sleeping, if she makes it to 2 hours I consider it a blessing. She doesn't cry when put on her back, she just wakes up after about 1h45min and cries. I usually nurse her back to sleep, but sometimes rocking will do the trick. She sleeps in a dark room with white noise, after a bedtime routine, etc etc..

She doesn't throw/spit up too much, at most once a day. But she does do the 'silent' spit ups that you can't see because she swallows them. I don't know how many in a day, but I've tried to watch her closely and she perhaps does 2 or 3 of these a day.

Anyway, we finally got into see a pediatrician (there are only 2 in my town and the waiting list to see one is nearly 2 months) and I suggested that it may be silent reflux. The doc agreed and gave us a prescription for prevacid.

But here's the thing: that night, 10 minutes after giving my LO her 1st dose of prevacid (which she took like a champ), I had this horrible gut feeling that she should'nt be taking it. I suddenly feel like silent reflux isn't to blame and I don't want to overmedicate when it isn't necessary. When I made the appointment 2 months ago, her crying at the boob was near-constant, but she was also overtired and fighting her naps and her bedtime a lot. Since then, it's gotten less worse and less dramatic and it feels like it's improving, slowly.

I am practically delirious from lack of sleep and I don't know what to do about this whole thing. It doesn't seem obvious or clear-cut as to the cause of her upsets and lack of sleep. Should I just give her the prevacid and see if I see improvement? I'm not usually anti-medication, so this is unlike me. Should I just wait it out some more, since babies often outgrow reflux? Otherwise she's a happy baby.