Need help with cap gains taxes

I may have made a mistake but at this point the damage is done. Earlier this year I sold some of my etfs and will owe approx $8k in long term capital gains taxes. Do I need to mail in a quarterly tax payment on these gains or is it ok to wait to deal with it during tax season? I typically get refunds in the 8k range so it’ll end up being a wash with my refund. Are there any moves I can reduce this tax before tax time this year. I sold a portion of my holdings to payoff my house. I know it doesn’t make financial sense but it’s what I wanted to do and the damage is done.