I went to watch my girl friend playing drums yesterday
I went watching my girl friend playing drums yesterday
First , is the last sentence correct? What is the difference between go + gerund and go + infinitive?
The expression "go + gerund " is used for individual recreational activities and sports adventure. This is why you can say "go boating, go sailing, go bowling, go scuba diving, go shopping, go camping."
On that explanation, I can say if Watching her playing guitars is a recreational activity for you, then it's correct to say the number two. If not, then it's incorrect.