After 4 month, can I get side effect?

[devz]

I’m 24yo, I started minoxidil 2% 1application day and I never have sides till now. I woke up during sleep or is hard to me sleep well, If I stand up after I woke up is like I got a bit of headache. No idea if is minoxidil but is really sad have sides only with 2% treatment and after 4 months