I need advise please

Ok I'm not great with this stuff I've never felt down I've always been happy about my life but the last month I cant sleep hardly eat and I always feel very lonely all the time I'm 24 I ain't had a girlfriend since I was 16 I've tried online and tried meeting people nothing works I think I'm just scared I'm going to be alone forever my friends have girlfriends and some even have familys now so I try talk to them but they cant understand. I just cant do this no more I can hardly sleep and when I try it feels like I'm being suffocated I'm always thinking about being with someone and I have no clue what to do anymore