Why is my car unresponsive: desperate for direction
Okay I have a 4 door 2008 Nissan Altima. I just pumped hundreds of $$ into fixing a valve oil leak, on top of other things. Once fixed, the car drove smoothly for all of 48 hrs before it became completely unresponsive. So unresponsive that I can’t lock my doors, I can’t pop my truck, interior or exterior lights do not turn on, the car does not crank or start, no flashing lights what so ever. We attempted to give it a jump and the most that happened was it cranked but then quickly shut off again. I then let it sit for a few minutes and a quick light appeared and then disappeared. But for the most part no action outside of that. Also something to note, I just bought a new battery less than 3 months ago. So it’s fairly new. Could it be a possible fuse blown ? Or is it much deeper than that? Please give me some direction, I’m I so hopeless and ad defeated at this point.