Is it okay to use a bikini bra and a board shorts? instead of using the underwear of the bikini? i dont feel w?

we're goin to the beach and i dont know what to wear. well. im fat now so i dont feel like wearing the underwear of my bikini. so im planning to use my bikini bra and a board shorts. is it okay? of course i have to match the color. but is it awkward? or something? please help me...... i cant decide. :)