Maybe it's me being a noob at DIY. I mixed my first batch of juices. Just single flavours at 5%. All TFA flavours. Mixed 50ml of each with 3mg nic strength. Been vaping them for about 2 weeks and although some of the flavours were very light, I could taste them. Now in the past 3 days, they've all gotten extremely harsh and peppery to the point where I can't taste the actual flavour. Does the nic go bad so quickly in DIY juices?