Deep Cleaning Opinion

Hello r/Dentistry! I recently changed my dentist due to a move and I went in for my usual 6 month check up with this new dentist. My previous dentist which I had my whole life (26 years) always mentioned I had minor gum disease due to the bleeding and redness from my gums but never mentioned anything about "Deep Cleaning". Today, I went for a check up/cleaning at my new dentist, and she performed the test where she touched my gums and would say 2/3/4/5 (3/4 was the average). She then did what she called "Deep Cleaning" which I never had done at my old dentist. It was painful and there was a lot of blood, but she said it was necessary and further explained proper brushing techniques etc. She basically was shooting liquid deep into my gums 3-4 rounds of it with one type of liquid she said to clean and the second was minty (I don't have much more specific details).

My questions for you all are:

• How effective is deep cleaning for my situation (how often will I need it? Every 6 months?)
• I was charged $150 for the session which included X-rays (I unfortunately do not have dental insurance) - did I get ripped off?

Any information would be appreciated!