I think my husband is cheating

So my husband and I haven't had sex in like 2 weeks which is not normal for us. And around the last time we had sex he accused me of cheating. He doesn't look at me the same. Even my friends are noticing because my friends and I used to share sex stories all the time and mow I am silent. (My husband doesn't care about the things I tell my friends) and he has been really protective of his phone lately. Idk someone tell me that I am over thinking this.