How should I curb my intrusive thoughts and the sexual imagery?

I'm 38 days into my streak (longest I've ever gone). Today, the substantial brain fog I've had for weeks (if not months) was lifted and I feel far more clear minded, but not as good as I used to be partly because of the thoughts and imagery. Right before I started NoFap after 5 or so years of PMO, I've been having intrusive thoughts and recently I'm starting to have more consistent imagery flashbacks. They don't affect my urges in any shape or form but they are distracting.

I haven't been productive for the following months since the intrusive thoughts started, in the sense that all I've been doing for 12 months or so is browsing the internet and watching TV and movies here and there which doesn't really keep my brain busy and I ultimately suspect, far more susceptible to the imagery and thoughts. Either way, I'm not really sure about all of this and so getting any insight would be great (How long would It take to disappear, how do i curb them and anything else you think is worth mentioning).