helpppp please

hey ladies, the last time I had sex was five months ago. I have gotten my period 4 times since then. The first three times were completely normal. After the third time I developed what I think was a yeast infection I didn’t go to the doctor because I thought I would let it go away on its own (It did). When I got the 4th period, it was different than usual. The blood was lighter almost a pink or light red and there was a fair amount but not as much as usual. I was supposed to get my period a couple days ago and it’s still not here. I’ve had my period for about 7 or 8 years and I’ve only ever missed my period one time and it was before I was ever sexually active. Any advice? I don’t think I could be pregnant right? It’s been 5 months. I’m a college student and I wanted to go to the doctor but I tried to make an appointment at my college health center and they only have a few choices you can pick from, none of them were to see a gynecologist, also I’m on my parents insurance and I dont want them to see why I went. Can anyone help me? Idk why I’m not getting my period and it’s really worrying me.