Brupropian Dose Changes

Hi everyone! It's been awhile since I posted, mostly for good reasons.. I had been doing well for the summer months on my medications and things seemed really good.I was taking Lexapro and Bruprion but because I was doing so well my Dr. thought I could stop the lexapro and see how well just being on Bruproprion would work. I stopped the Lexapro about 2 months ago.. So continuing on my 300mg of Brupropion daily things still seemed okay so about 4-6 weeks ago I cut that dosage in half to 150mg. I started to noticed things beginning to go downhill again but I was hanging in there.. then after this weekend I felt like I had relapsed to back where I started before any meds, wanted to die, didn't want to be near anyone, felt so depressed etc... So on Tuesday I upped my dosage of Bruproprion to 225mg to see if that would help, I know it's only been 3 days but my question to anyone that can help is : Is this normal to feel worse a couple days after making your dose higher again and how long til it gets better? I thought since I've always had it in my system it would just make things better and it wouldn't be like starting all over again.. Any feedback would be great!

Thank you