*Trigger Warning (Graphic)* Overthinking is Killing Me

Lately my overthinking is developing in ways that are just... weird ;s and I'm worried.
Divagating is actually like a routinary thing for me since long ago... Just rambling from thought to thought without having any specific focus. It usually end ups giving me a negative overview of the world and life in general, but nothing I can't control. However, a few weeks ago this turned into a scary mess... It felt like 500 diferent voices talking to me at the same time and at incredible speeds. I couldn't understand any of them. Of course, I knew they were product of my own mind... But I actually felt like I was able to hear my own thoughts racing quickly in many different random voices... It was exhausting and made me nervous and kindda anxious. This is the first time I "hear" something unreal.
This sort of thing have not repeated since then, but I do constantly get very graphic thoughts... images about my death/suicide and self-harm. And they tempt and trigger me to try more dangerous behaviours like cutting from the base of my thumb all the way down to the crook of my elbow... It's really hard to try not to cut at all when I'm overly focused about controling the risks, not to try it this way.
The suicide images are specially worrying because they come to mind when seeing very common everyday objects: cars, ropes, hair dryiers, water, whatever. So I'm being haunted by these thoughts in a daily basis.
I no longer know if I'm okay... I don't know how long will it take till these are not just 'thoughts' anymore.
Today I skipped the appointment to see my psychologist (who I see once every two weeks) due to money and transportation problems. I was anxious about our meeting today but I really feel like I needed it. I'm sure my parents think I'm going just because "I enjoy it" not because I have some real issues.
Sorry, I don't mean to sound like... self-pitty or exaggerated drama. I'm just... scared of myself.