Struggling with side effects

"I was instructed by my psychiatrist to start CBD oil on top of my Cymbalta because I can’t tolerate going up anymore on the dosage. First weeks of using CBD from reparable brands I felt great. Lifted my mood, gave me energy, could take multiple dosages of it a day and felt fine. But now it’s making me really sleepy, even at low dosages, I’m talking about less than 5 mg here. I take it sublingually. It’s full spectrum CBD too. If I stop taking it, the low mood will start coming back, so it is working for that but the triedness is becoming a problem. It was working so good that I felt like I’d be able to reduce my antidepressant one day. Now I feel I can’t tolerate the CBD oil. Btw, if I take it at night, I either have where I’m tired the next day or sometimes (and this is the weirdest thing) it’ll wake me up. Still is all very frustrating. "