Is it normal for your smell/taste to randomly change all the time?

For about a year or so, I'll randomly lose my sense of taste/everything will suddenly taste bad (i.e. juice tastes like metal or bread tastes like plastic). Sometimes it happens after I sneeze, sometimes it comes out of nowhere. I will sometimes get headaches as well but not always. The only cure I've found for when this happens is to just sleep it off... otherwise I just can't eat anything until it goes away. The only way I can taste the food normally when this happens is if I plug my nose and press the food really hard against my tongue which is not really fun.

I'm only 20, I don't have any serious health issues that I'm aware of, and I consider myself to be pretty healthy. Should I see a doctor about this? Is this normal? Please help!! I can't find any answers on google :/