Nikon film SLR shutter won't close?

I was using it fine, and after i put a new roll in and took my first shot the shutter stayed open for about a minute before randomly closing. I tried to make adjustments but this same thing happened a few more times. I wound the film and put it back in thinking it had something to do with that, and then it happened again. I didn't take any pictures for a few minutes, and then it just worked like normal again. Halfway through that roll it happened again, except now it won't shut at all

What happens when you take photos outdoors in bright sun?

It sounds like you are trying to take photos indoors in low light and the camera is trying to keep the shutter open long enough to get a properly exposed shot.

Sounds like time to call Nikon for repairs.

If it's happening even in bright light, then it may have sticky shutter release magnets. A fairly common issue with old SLRs

Depending on your model, you may be able to get a camera repair technician to sort it out as part of a general camera maintenance service, or you may have to do it yourself. If you search online for "shutter magnets" and your exact model you'll often find that someone has detailed instructions or even a "how-to" video which they've uploaded to the web.