it's always one thing after another....*sort of explicit*

Lately I have had very sexual intrusive thoughts regarding mainly pet. Sometimes family. But mainly the ones with pets sometimes cause physical sensations. I do have OCD so I know it happens. But my issue is that ever since they got bad,I can not...well...masturbate? I feel if I do then it's because the thought caused arousal. When I usually want to,I think of normal sexual things that would turn a person on. But is it wrong to act on those if right before I was having the bad ones which I think cause physical symptoms? Thinking the normal ones after is what I'm seriously hoping is what really gets me to the point where I really want to...you know. I don't want to do it towards the bad ones. I feel guilty doing it at all cause I feel like the intrusive ones are what really lead to it.